diff --git a/pkg/analysis_server/lib/src/computer/computer_highlights.dart b/pkg/analysis_server/lib/src/computer/computer_highlights.dart
index a2fe59310c9..3af81c417db 100644
--- a/pkg/analysis_server/lib/src/computer/computer_highlights.dart
+++ b/pkg/analysis_server/lib/src/computer/computer_highlights.dart
@@ -223,7 +223,7 @@ class DartUnitHighlightsComputer {
     var element = node.writeOrReadElement;
     if (element is LocalVariableElement) {
       var elementType = element.type;
-      if (elementType.isDynamic) {
+      if (elementType is DynamicType) {
         var type = node.inDeclarationContext()
             ? HighlightRegionType.DYNAMIC_LOCAL_VARIABLE_DECLARATION
             : HighlightRegionType.DYNAMIC_LOCAL_VARIABLE_REFERENCE;
@@ -232,7 +232,7 @@ class DartUnitHighlightsComputer {
     }
     if (element is ParameterElement) {
       var elementType = element.type;
-      if (elementType.isDynamic) {
+      if (elementType is DynamicType) {
         var type = node.inDeclarationContext()
             ? HighlightRegionType.DYNAMIC_PARAMETER_DECLARATION
             : HighlightRegionType.DYNAMIC_PARAMETER_REFERENCE;
@@ -601,7 +601,7 @@ class DartUnitHighlightsComputer {
 
   static bool _isDynamicExpression(Expression e) {
     var type = e.staticType;
-    return type != null && type.isDynamic;
+    return type != null && type is DynamicType;
   }
 }
 
@@ -1162,7 +1162,7 @@ class _DartUnitHighlightsComputerVisitor extends RecursiveAstVisitor<void> {
   void visitNamedType(NamedType node) {
     var type = node.type;
     if (type != null) {
-      var isDynamic = type.isDynamic && node.name2.lexeme == 'dynamic';
+      var isDynamic = type is DynamicType && node.name2.lexeme == 'dynamic';
       var isNever = type is NeverType;
       if (isDynamic || isNever) {
         computer._addRegion_token(
diff --git a/pkg/analysis_server/lib/src/computer/computer_hover.dart b/pkg/analysis_server/lib/src/computer/computer_hover.dart
index 54ae90dba00..0ff13df36a2 100644
--- a/pkg/analysis_server/lib/src/computer/computer_hover.dart
+++ b/pkg/analysis_server/lib/src/computer/computer_hover.dart
@@ -173,7 +173,7 @@ class DartUnitHoverComputer {
           staticType = element.type;
         } else if (parent is MethodInvocation && parent.methodName == node) {
           staticType = parent.staticInvokeType;
-          if (staticType != null && staticType.isDynamic) {
+          if (staticType != null && staticType is DynamicType) {
             staticType = null;
           }
         } else if (node is PatternFieldName && parent is PatternField) {
diff --git a/pkg/analysis_server/lib/src/services/completion/dart/feature_computer.dart b/pkg/analysis_server/lib/src/services/completion/dart/feature_computer.dart
index b9cfc08f34a..8ebf5801378 100644
--- a/pkg/analysis_server/lib/src/services/completion/dart/feature_computer.dart
+++ b/pkg/analysis_server/lib/src/services/completion/dart/feature_computer.dart
@@ -166,7 +166,7 @@ class FeatureComputer {
     final contextType = node.accept(
       _ContextTypeVisitor(typeProvider, offset),
     );
-    if (contextType == null || contextType.isDynamic) {
+    if (contextType == null || contextType is DynamicType) {
       return null;
     }
     return typeSystem.resolveToBound(contextType);
diff --git a/pkg/analysis_server/lib/src/services/completion/dart/type_member_contributor.dart b/pkg/analysis_server/lib/src/services/completion/dart/type_member_contributor.dart
index 2b7a32b28a5..d5d440c805d 100644
--- a/pkg/analysis_server/lib/src/services/completion/dart/type_member_contributor.dart
+++ b/pkg/analysis_server/lib/src/services/completion/dart/type_member_contributor.dart
@@ -129,7 +129,7 @@ class TypeMemberContributor extends DartCompletionContributor {
     var type = expressionType != null
         ? request.libraryElement.typeSystem.resolveToBound(expressionType)
         : null;
-    if (type == null || type.isDynamic) {
+    if (type == null || type is DynamicType) {
       // If the expression does not provide a good type, then attempt to get a
       // better type from the element.
       if (expression is Identifier) {
@@ -141,7 +141,7 @@ class TypeMemberContributor extends DartCompletionContributor {
         } else if (elem is LocalVariableElement) {
           type = elem.type;
         }
-        if ((type == null || type.isDynamic) &&
+        if ((type == null || type is DynamicType) &&
             expression is SimpleIdentifier) {
           // If the element does not provide a good type, then attempt to get a
           // better type from a local declaration.
diff --git a/pkg/analysis_server/lib/src/services/completion/dart/utilities.dart b/pkg/analysis_server/lib/src/services/completion/dart/utilities.dart
index da264a16d89..295c6057ed0 100644
--- a/pkg/analysis_server/lib/src/services/completion/dart/utilities.dart
+++ b/pkg/analysis_server/lib/src/services/completion/dart/utilities.dart
@@ -211,7 +211,7 @@ String getRequestLineIndent(DartCompletionRequest request) {
 }
 
 String getTypeString(DartType type, {required bool withNullability}) {
-  if (type.isDynamic) {
+  if (type is DynamicType) {
     return '';
   } else {
     return '${type.getDisplayString(withNullability: withNullability)} ';
@@ -245,7 +245,7 @@ String? nameForType(SimpleIdentifier identifier, TypeAnnotation? declaredType) {
   }
 
   // If the type is unresolved, use the declared type.
-  if (type.isDynamic) {
+  if (type is DynamicType) {
     if (declaredType is NamedType) {
       return declaredType.qualifiedName;
     }
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/add_diagnostic_property_reference.dart b/pkg/analysis_server/lib/src/services/correction/dart/add_diagnostic_property_reference.dart
index 5c39b67b0f5..dc204f52b22 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/add_diagnostic_property_reference.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/add_diagnostic_property_reference.dart
@@ -79,7 +79,7 @@ class AddDiagnosticPropertyReference extends CorrectionProducer {
       constructorId = 'TransformProperty';
     } else {
       constructorId = 'DiagnosticsProperty';
-      if (!type.isDynamic) {
+      if (type is! DynamicType) {
         typeArgs = [type];
       }
     }
@@ -94,7 +94,7 @@ class AddDiagnosticPropertyReference extends CorrectionProducer {
         builder.write('<');
         builder.writeTypes(typeArgs);
         builder.write('>');
-      } else if (type.isDynamic) {
+      } else if (type is DynamicType) {
         TypeAnnotation? declType;
         final decl = node.thisOrAncestorOfType<VariableDeclarationList>();
         if (decl != null) {
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/add_return_type.dart b/pkg/analysis_server/lib/src/services/correction/dart/add_return_type.dart
index 97e7e9480b6..ae412cbfe9d 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/add_return_type.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/add_return_type.dart
@@ -67,9 +67,9 @@ class AddReturnType extends CorrectionProducer {
 
     final insertBeforeEntity_final = insertBeforeEntity;
     await builder.addDartFileEdit(file, (builder) {
-      if (returnType.isDynamic || builder.canWriteType(returnType)) {
+      if (returnType is DynamicType || builder.canWriteType(returnType)) {
         builder.addInsertion(insertBeforeEntity_final.offset, (builder) {
-          if (returnType.isDynamic) {
+          if (returnType is DynamicType) {
             builder.write('dynamic');
           } else {
             builder.writeType(returnType);
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/convert_to_map_literal.dart b/pkg/analysis_server/lib/src/services/correction/dart/convert_to_map_literal.dart
index 2946e196144..6c86e595226 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/convert_to_map_literal.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/convert_to_map_literal.dart
@@ -58,8 +58,8 @@ class ConvertToMapLiteral extends CorrectionProducer {
           creation.thisOrAncestorOfType<VariableDeclarationList>();
       if (variableDeclarationList?.type == null) {
         staticTypeArguments = type.typeArguments;
-        if (staticTypeArguments.first.isDynamic &&
-            staticTypeArguments.last.isDynamic) {
+        if (staticTypeArguments.first is DynamicType &&
+            staticTypeArguments.last is DynamicType) {
           staticTypeArguments = null;
         }
       }
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/convert_to_normal_parameter.dart b/pkg/analysis_server/lib/src/services/correction/dart/convert_to_normal_parameter.dart
index 2084c65193d..28eb6a87d64 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/convert_to_normal_parameter.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/convert_to_normal_parameter.dart
@@ -5,6 +5,7 @@
 import 'package:analysis_server/src/services/correction/assist.dart';
 import 'package:analysis_server/src/services/correction/dart/abstract_producer.dart';
 import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer_plugin/utilities/assist/assist.dart';
 import 'package:analyzer_plugin/utilities/change_builder/change_builder_core.dart';
 import 'package:analyzer_plugin/utilities/range_factory.dart';
@@ -30,7 +31,7 @@ class ConvertToNormalParameter extends CorrectionProducer {
 
     await builder.addDartFileEdit(file, (builder) {
       // replace parameter
-      if (type.isDynamic) {
+      if (type is DynamicType) {
         builder.addSimpleReplacement(range.node(parameter), name);
       } else {
         builder.addReplacement(range.node(parameter), (builder) {
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/replace_return_type_iterable.dart b/pkg/analysis_server/lib/src/services/correction/dart/replace_return_type_iterable.dart
index 1c2b1779b40..4b8f77a6d69 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/replace_return_type_iterable.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/replace_return_type_iterable.dart
@@ -5,6 +5,7 @@
 import 'package:analysis_server/src/services/correction/dart/abstract_producer.dart';
 import 'package:analysis_server/src/services/correction/fix.dart';
 import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer_plugin/utilities/change_builder/change_builder_core.dart';
 import 'package:analyzer_plugin/utilities/fixes/fixes.dart';
 import 'package:analyzer_plugin/utilities/range_factory.dart';
@@ -27,7 +28,7 @@ class ReplaceReturnTypeIterable extends CorrectionProducer {
       return;
     }
     var type = typeAnnotation.type;
-    if (type == null || type.isDynamic || type.isDartCoreIterable) {
+    if (type == null || type is DynamicType || type.isDartCoreIterable) {
       return;
     }
     _typeArgument = utils.getNodeText(typeAnnotation);
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/replace_return_type_stream.dart b/pkg/analysis_server/lib/src/services/correction/dart/replace_return_type_stream.dart
index bc38772be7d..6784c93ea06 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/replace_return_type_stream.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/replace_return_type_stream.dart
@@ -5,6 +5,7 @@
 import 'package:analysis_server/src/services/correction/dart/abstract_producer.dart';
 import 'package:analysis_server/src/services/correction/fix.dart';
 import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer_plugin/utilities/change_builder/change_builder_core.dart';
 import 'package:analyzer_plugin/utilities/fixes/fixes.dart';
 import 'package:analyzer_plugin/utilities/range_factory.dart';
@@ -27,7 +28,7 @@ class ReplaceReturnTypeStream extends CorrectionProducer {
       return;
     }
     var type = typeAnnotation.type;
-    if (type == null || type.isDynamic || type.isDartAsyncStream) {
+    if (type == null || type is DynamicType || type.isDartAsyncStream) {
       return;
     }
     _typeArgument = utils.getNodeText(typeAnnotation);
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/replace_with_var.dart b/pkg/analysis_server/lib/src/services/correction/dart/replace_with_var.dart
index abb1a1044ee..111d0a29e88 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/replace_with_var.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/replace_with_var.dart
@@ -6,6 +6,7 @@ import 'package:analysis_server/src/services/correction/assist.dart';
 import 'package:analysis_server/src/services/correction/dart/abstract_producer.dart';
 import 'package:analysis_server/src/services/correction/fix.dart';
 import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/src/dart/ast/extensions.dart';
 import 'package:analyzer_plugin/utilities/assist/assist.dart';
 import 'package:analyzer_plugin/utilities/change_builder/change_builder_core.dart';
@@ -124,7 +125,7 @@ class ReplaceWithVar extends CorrectionProducer {
   /// Return `true` if the type in the [node] can be replaced with `var`.
   bool _canConvertVariableDeclarationList(VariableDeclarationList node) {
     final staticType = node.type?.type;
-    if (staticType == null || staticType.isDynamic) {
+    if (staticType == null || staticType is DynamicType) {
       return false;
     }
     for (final child in node.variables) {
@@ -147,7 +148,7 @@ class ReplaceWithVar extends CorrectionProducer {
       } else if (parent is ForEachPartsWithDeclaration) {
         var loopVariableType = parent.loopVariable.type;
         var staticType = loopVariableType?.type;
-        if (staticType == null || staticType.isDynamic) {
+        if (staticType == null || staticType is DynamicType) {
           return false;
         }
         final iterableType = parent.iterable.typeOrThrow;
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/split_variable_declaration.dart b/pkg/analysis_server/lib/src/services/correction/dart/split_variable_declaration.dart
index f2f5c81e0ad..454ed2ba827 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/split_variable_declaration.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/split_variable_declaration.dart
@@ -6,6 +6,7 @@ import 'package:_fe_analyzer_shared/src/scanner/token.dart';
 import 'package:analysis_server/src/services/correction/assist.dart';
 import 'package:analysis_server/src/services/correction/dart/abstract_producer.dart';
 import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer_plugin/utilities/assist/assist.dart';
 import 'package:analyzer_plugin/utilities/change_builder/change_builder_core.dart';
 import 'package:analyzer_plugin/utilities/range_factory.dart';
@@ -53,7 +54,7 @@ class SplitVariableDeclaration extends CorrectionProducer {
     await builder.addDartFileEdit(file, (builder) {
       if (variableList.type == null) {
         final type = variable.declaredElement!.type;
-        if (!type.isDynamic && keyword != null) {
+        if (type is! DynamicType && keyword != null) {
           if (!builder.canWriteType(type)) {
             return;
           }
diff --git a/pkg/analysis_server/lib/src/services/correction/fix/data_driven/element_matcher.dart b/pkg/analysis_server/lib/src/services/correction/fix/data_driven/element_matcher.dart
index 96c8e57a80b..c027114cabc 100644
--- a/pkg/analysis_server/lib/src/services/correction/fix/data_driven/element_matcher.dart
+++ b/pkg/analysis_server/lib/src/services/correction/fix/data_driven/element_matcher.dart
@@ -544,7 +544,7 @@ class _MatcherBuilder {
       if (type != null) {
         if (type is InterfaceType) {
           return type.element.name;
-        } else if (type.isDynamic) {
+        } else if (type is DynamicType) {
           // The name is likely to be undefined.
           return target.name;
         }
diff --git a/pkg/analysis_server/lib/src/services/correction/name_suggestion.dart b/pkg/analysis_server/lib/src/services/correction/name_suggestion.dart
index 98f97215bde..9fdb95fe68d 100644
--- a/pkg/analysis_server/lib/src/services/correction/name_suggestion.dart
+++ b/pkg/analysis_server/lib/src/services/correction/name_suggestion.dart
@@ -58,7 +58,7 @@ List<String> getVariableNameSuggestionsForExpression(DartType? expectedType,
     }
   }
   // use type
-  if (expectedType != null && !expectedType.isDynamic) {
+  if (expectedType != null && expectedType is! DynamicType) {
     if (expectedType.isDartCoreInt) {
       _addSingleCharacterName(excluded, res, 0x69);
     } else if (expectedType.isDartCoreDouble) {
diff --git a/pkg/analysis_server/lib/src/services/refactoring/legacy/extract_method.dart b/pkg/analysis_server/lib/src/services/refactoring/legacy/extract_method.dart
index f1b1476f093..a3c424e2f26 100644
--- a/pkg/analysis_server/lib/src/services/refactoring/legacy/extract_method.dart
+++ b/pkg/analysis_server/lib/src/services/refactoring/legacy/extract_method.dart
@@ -792,7 +792,7 @@ class ExtractMethodRefactoringImpl extends RefactoringImpl
       } else {
         returnType = 'void';
       }
-    } else if (returnTypeObj.isDynamic) {
+    } else if (returnTypeObj is DynamicType) {
       variableType = '';
       if (_hasAwait) {
         returnType = _getTypeCode(typeProvider.futureDynamicType);
diff --git a/pkg/analysis_server/tool/code_completion/implicit_type_declarations.dart b/pkg/analysis_server/tool/code_completion/implicit_type_declarations.dart
index 7e3801cba82..c857586edab 100644
--- a/pkg/analysis_server/tool/code_completion/implicit_type_declarations.dart
+++ b/pkg/analysis_server/tool/code_completion/implicit_type_declarations.dart
@@ -104,10 +104,11 @@ class ImpliedTypeCollector extends RecursiveAstVisitor<void> {
   void handleVariableDeclaration(VariableDeclaration node, DartType? dartType) {
     // If some untyped variable declaration
     if (node.equals != null && dartType == null ||
-        (dartType != null && (dartType.isDynamic || dartType is VoidType))) {
+        (dartType != null &&
+            (dartType is DynamicType || dartType is VoidType))) {
       // And if we can determine the type on the RHS of the variable declaration
       var rhsType = node.initializer?.staticType;
-      if (rhsType != null && !rhsType.isDynamic) {
+      if (rhsType != null && rhsType is! DynamicType) {
         // Record the name with the type.
         data.recordImpliedType(
           node.name.lexeme,
diff --git a/pkg/analysis_server/tool/code_completion/relevance_metrics.dart b/pkg/analysis_server/tool/code_completion/relevance_metrics.dart
index 7609882cdc7..faf6d342ffa 100644
--- a/pkg/analysis_server/tool/code_completion/relevance_metrics.dart
+++ b/pkg/analysis_server/tool/code_completion/relevance_metrics.dart
@@ -1661,9 +1661,9 @@ class RelevanceDataCollector extends RecursiveAstVisitor<void> {
       var overrideType = overrideParameter?.type;
       var overriddenType = overriddenParameter?.type;
       if (overrideType == null ||
-          overrideType.isDynamic ||
+          overrideType is DynamicType ||
           overriddenType == null ||
-          overriddenType.isDynamic) {
+          overriddenType is DynamicType) {
         return;
       }
       _recordTypeRelationships(
@@ -1764,7 +1764,7 @@ class RelevanceDataCollector extends RecursiveAstVisitor<void> {
   /// in the expression match the type of the associated parameter.
   void _recordTypeMatch(Expression argument) {
     var parameterType = argument.staticParameterElement?.type;
-    if (parameterType == null || parameterType.isDynamic) {
+    if (parameterType == null || parameterType is DynamicType) {
       return;
     }
     if (parameterType is FunctionType) {
diff --git a/pkg/analysis_server/tool/code_completion/visitors.dart b/pkg/analysis_server/tool/code_completion/visitors.dart
index 5b681ab123f..edf164d9653 100644
--- a/pkg/analysis_server/tool/code_completion/visitors.dart
+++ b/pkg/analysis_server/tool/code_completion/visitors.dart
@@ -11,6 +11,7 @@ import 'package:analyzer/dart/ast/syntactic_entity.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
 import 'package:analyzer/dart/element/element.dart' as element;
+import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/source/line_info.dart';
 
 class ExpectedCompletion {
@@ -773,7 +774,7 @@ class ExpectedCompletionsVisitor extends RecursiveAstVisitor<void> {
 
     // If the type of the SimpleIdentifier is dynamic, don't include.
     var staticType = node.staticType;
-    if (staticType != null && staticType.isDynamic) {
+    if (staticType != null && staticType is DynamicType) {
       return false;
     }
 
diff --git a/pkg/analyzer/CHANGELOG.md b/pkg/analyzer/CHANGELOG.md
index ab2fa2e7ec6..465dc5acc06 100644
--- a/pkg/analyzer/CHANGELOG.md
+++ b/pkg/analyzer/CHANGELOG.md
@@ -1,3 +1,6 @@
+## 5.12.0-dev
+* Deprecated `DartType.isDynamic`, use `is DynamicType` instead.
+
 ## 5.11.1
 * Restore previously published `finalKeyword`, `interfaceKeyword` and
   `sealedKeyword` of `MixinElement`. We added them preliminary while
diff --git a/pkg/analyzer/lib/dart/element/type.dart b/pkg/analyzer/lib/dart/element/type.dart
index e10fac8b5a7..41f303615f8 100644
--- a/pkg/analyzer/lib/dart/element/type.dart
+++ b/pkg/analyzer/lib/dart/element/type.dart
@@ -124,6 +124,7 @@ abstract class DartType {
   bool get isDartCoreType;
 
   /// Return `true` if this type represents the type 'dynamic'.
+  @Deprecated('Use `is DynamicType` instead')
   bool get isDynamic;
 
   /// Return `true` if this type represents the type 'void'.
diff --git a/pkg/analyzer/lib/src/dart/element/display_string_builder.dart b/pkg/analyzer/lib/src/dart/element/display_string_builder.dart
index 0497a7eb9e4..e003ba4502d 100644
--- a/pkg/analyzer/lib/src/dart/element/display_string_builder.dart
+++ b/pkg/analyzer/lib/src/dart/element/display_string_builder.dart
@@ -381,7 +381,7 @@ class ElementDisplayStringBuilder {
     }
 
     if (skipAllDynamicArguments) {
-      if (typeArguments.every((t) => t.isDynamic)) {
+      if (typeArguments.every((t) => t is DynamicType)) {
         return;
       }
     }
diff --git a/pkg/analyzer/lib/src/dart/element/type.dart b/pkg/analyzer/lib/src/dart/element/type.dart
index 7ebde9eda89..28047fa9613 100644
--- a/pkg/analyzer/lib/src/dart/element/type.dart
+++ b/pkg/analyzer/lib/src/dart/element/type.dart
@@ -48,6 +48,7 @@ class DynamicTypeImpl extends TypeImpl implements DynamicType {
   @override
   int get hashCode => 1;
 
+  @Deprecated('Use `is DynamicType` instead')
   @override
   bool get isDynamic => true;
 
@@ -362,7 +363,7 @@ class FunctionTypeImpl extends TypeImpl implements FunctionType {
         return null;
       }
 
-      if (!bound2.isDynamic) {
+      if (bound2 is! DynamicType) {
         pFresh.bound = bound2;
       }
     }
@@ -1247,6 +1248,7 @@ abstract class TypeImpl implements DartType {
   @override
   bool get isDartCoreType => false;
 
+  @Deprecated('Use `is DynamicType` instead')
   @override
   bool get isDynamic => false;
 
diff --git a/pkg/analyzer/lib/src/dart/element/type_schema.dart b/pkg/analyzer/lib/src/dart/element/type_schema.dart
index d3916a2d2e6..176b882479a 100644
--- a/pkg/analyzer/lib/src/dart/element/type_schema.dart
+++ b/pkg/analyzer/lib/src/dart/element/type_schema.dart
@@ -32,6 +32,7 @@ class UnknownInferredType extends TypeImpl {
   @override
   int get hashCode => 1;
 
+  @Deprecated('Use `is UnknownInferredType` instead')
   @override
   bool get isDynamic => true;
 
diff --git a/pkg/analyzer/lib/src/dart/element/type_system.dart b/pkg/analyzer/lib/src/dart/element/type_system.dart
index ba0bdf5c86a..5706755ae44 100644
--- a/pkg/analyzer/lib/src/dart/element/type_system.dart
+++ b/pkg/analyzer/lib/src/dart/element/type_system.dart
@@ -914,7 +914,7 @@ class TypeSystemImpl implements TypeSystem {
 
     // Now handle NNBD default behavior, where we disable non-dynamic downcasts.
     if (isNonNullableByDefault) {
-      return fromType.isDynamic;
+      return fromType is DynamicType;
     }
 
     // Don't allow implicit downcasts between function types
@@ -1243,7 +1243,10 @@ class TypeSystemImpl implements TypeSystem {
 
   @override
   bool isNonNullable(DartType type) {
-    if (type.isDynamic || type is VoidType || type.isDartCoreNull) {
+    if (type is DynamicType ||
+        type is UnknownInferredType ||
+        type is VoidType ||
+        type.isDartCoreNull) {
       return false;
     } else if (type is TypeParameterTypeImpl && type.promotedBound != null) {
       return isNonNullable(type.promotedBound!);
@@ -1284,7 +1287,10 @@ class TypeSystemImpl implements TypeSystem {
 
   @override
   bool isNullable(DartType type) {
-    if (type.isDynamic || type is VoidType || type.isDartCoreNull) {
+    if (type is DynamicType ||
+        type is UnknownInferredType ||
+        type is VoidType ||
+        type.isDartCoreNull) {
       return true;
     } else if (type is TypeParameterTypeImpl && type.promotedBound != null) {
       return isNullable(type.promotedBound!);
@@ -1326,7 +1332,10 @@ class TypeSystemImpl implements TypeSystem {
 
   @override
   bool isStrictlyNonNullable(DartType type) {
-    if (type.isDynamic || type is VoidType || type.isDartCoreNull) {
+    if (type is DynamicType ||
+        type is UnknownInferredType ||
+        type is VoidType ||
+        type.isDartCoreNull) {
       return false;
     } else if (type.nullabilitySuffix != NullabilitySuffix.none) {
       return false;
@@ -1682,7 +1691,7 @@ class TypeSystemImpl implements TypeSystem {
         return null;
       }
 
-      if (!bound1.isDynamic) {
+      if (bound1 is! DynamicType) {
         freshTypeParameters[i].bound = bound1;
       }
     }
diff --git a/pkg/analyzer/lib/src/dart/resolver/binary_expression_resolver.dart b/pkg/analyzer/lib/src/dart/resolver/binary_expression_resolver.dart
index a4935f4316c..d87f8141202 100644
--- a/pkg/analyzer/lib/src/dart/resolver/binary_expression_resolver.dart
+++ b/pkg/analyzer/lib/src/dart/resolver/binary_expression_resolver.dart
@@ -13,6 +13,7 @@ import 'package:analyzer/error/listener.dart';
 import 'package:analyzer/src/dart/ast/ast.dart';
 import 'package:analyzer/src/dart/ast/extensions.dart';
 import 'package:analyzer/src/dart/element/type.dart';
+import 'package:analyzer/src/dart/element/type_schema.dart';
 import 'package:analyzer/src/dart/element/type_system.dart';
 import 'package:analyzer/src/dart/resolver/invocation_inference_helper.dart';
 import 'package:analyzer/src/dart/resolver/resolution_result.dart';
@@ -176,7 +177,9 @@ class BinaryExpressionResolver {
     var leftType = left.typeOrThrow;
 
     var rightContextType = contextType;
-    if (rightContextType == null || rightContextType.isDynamic) {
+    if (rightContextType == null ||
+        rightContextType is DynamicType ||
+        rightContextType is UnknownInferredType) {
       rightContextType = leftType;
     }
 
diff --git a/pkg/analyzer/lib/src/dart/resolver/flow_analysis_visitor.dart b/pkg/analyzer/lib/src/dart/resolver/flow_analysis_visitor.dart
index 9aa6ebcc959..684f8d10f5f 100644
--- a/pkg/analyzer/lib/src/dart/resolver/flow_analysis_visitor.dart
+++ b/pkg/analyzer/lib/src/dart/resolver/flow_analysis_visitor.dart
@@ -427,7 +427,7 @@ class TypeSystemOperations
   }
 
   @override
-  bool isDynamic(DartType type) => type.isDynamic;
+  bool isDynamic(DartType type) => type is DynamicType;
 
   @override
   bool isNever(DartType type) {
diff --git a/pkg/analyzer/lib/src/dart/resolver/function_expression_resolver.dart b/pkg/analyzer/lib/src/dart/resolver/function_expression_resolver.dart
index cde77546f02..2f7f97b1152 100644
--- a/pkg/analyzer/lib/src/dart/resolver/function_expression_resolver.dart
+++ b/pkg/analyzer/lib/src/dart/resolver/function_expression_resolver.dart
@@ -8,6 +8,7 @@ import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/src/dart/ast/ast.dart';
 import 'package:analyzer/src/dart/element/element.dart';
 import 'package:analyzer/src/dart/element/type.dart';
+import 'package:analyzer/src/dart/element/type_schema.dart';
 import 'package:analyzer/src/dart/element/type_system.dart';
 import 'package:analyzer/src/dart/resolver/invocation_inference_helper.dart';
 import 'package:analyzer/src/generated/migration.dart';
@@ -53,7 +54,7 @@ class FunctionExpressionResolver {
       if (instantiatedType is FunctionType) {
         _inferFormalParameters(node.parameters, instantiatedType);
         var returnType = instantiatedType.returnType;
-        if (!returnType.isDynamic) {
+        if (!(returnType is DynamicType || returnType is UnknownInferredType)) {
           imposedType = returnType;
         }
       }
@@ -91,7 +92,7 @@ class FunctionExpressionResolver {
     void inferType(ParameterElementImpl p, DartType inferredType) {
       // Check that there is no declared type, and that we have not already
       // inferred a type in some fashion.
-      if (p.hasImplicitType && p.type.isDynamic) {
+      if (p.hasImplicitType && p.type is DynamicType) {
         // If no type is declared for a parameter and there is a
         // corresponding parameter in the context type schema with type
         // schema `K`, the parameter is given an inferred type `T` where `T`
@@ -111,7 +112,7 @@ class FunctionExpressionResolver {
         } else {
           inferredType = _typeSystem.nonNullifyLegacy(inferredType);
         }
-        if (!inferredType.isDynamic) {
+        if (inferredType is! DynamicType) {
           p.type = inferredType;
         }
       }
diff --git a/pkg/analyzer/lib/src/dart/resolver/function_reference_resolver.dart b/pkg/analyzer/lib/src/dart/resolver/function_reference_resolver.dart
index 9fff0b34cf5..40720acb203 100644
--- a/pkg/analyzer/lib/src/dart/resolver/function_reference_resolver.dart
+++ b/pkg/analyzer/lib/src/dart/resolver/function_reference_resolver.dart
@@ -102,7 +102,7 @@ class FunctionReferenceResolver {
       prefixType = prefixElement.variable.type;
     }
 
-    if (prefixType != null && prefixType.isDynamic) {
+    if (prefixType is DynamicType) {
       _errorReporter.reportErrorForNode(
         CompileTimeErrorCode.GENERIC_METHOD_TYPE_INSTANTIATION_ON_DYNAMIC,
         function,
@@ -520,7 +520,7 @@ class FunctionReferenceResolver {
       return;
     } else {
       var targetType = target.staticType;
-      if (targetType != null && targetType.isDynamic) {
+      if (targetType is DynamicType) {
         _errorReporter.reportErrorForNode(
           CompileTimeErrorCode.GENERIC_METHOD_TYPE_INSTANTIATION_ON_DYNAMIC,
           node,
diff --git a/pkg/analyzer/lib/src/dart/resolver/legacy_type_asserter.dart b/pkg/analyzer/lib/src/dart/resolver/legacy_type_asserter.dart
index e29344f0c85..18d3cefb7d7 100644
--- a/pkg/analyzer/lib/src/dart/resolver/legacy_type_asserter.dart
+++ b/pkg/analyzer/lib/src/dart/resolver/legacy_type_asserter.dart
@@ -127,7 +127,7 @@ class LegacyTypeAsserter extends GeneralizingAstVisitor<void> {
       return;
     }
 
-    if (type.isDynamic || type is VoidType) {
+    if (type is DynamicType || type is VoidType) {
       return;
     }
 
diff --git a/pkg/analyzer/lib/src/dart/resolver/record_literal_resolver.dart b/pkg/analyzer/lib/src/dart/resolver/record_literal_resolver.dart
index 9612b79e848..a37b5360b78 100644
--- a/pkg/analyzer/lib/src/dart/resolver/record_literal_resolver.dart
+++ b/pkg/analyzer/lib/src/dart/resolver/record_literal_resolver.dart
@@ -128,7 +128,7 @@ class RecordLiteralResolver {
     field = _resolver.popRewrite()!;
 
     // Implicit cast from `dynamic`.
-    if (contextType != null && field.typeOrThrow.isDynamic) {
+    if (contextType != null && field.typeOrThrow is DynamicType) {
       field.staticType = contextType;
       if (field is NamedExpressionImpl) {
         field.expression.staticType = contextType;
diff --git a/pkg/analyzer/lib/src/dart/resolver/typed_literal_resolver.dart b/pkg/analyzer/lib/src/dart/resolver/typed_literal_resolver.dart
index de27813edea..5b60a57bc6c 100644
--- a/pkg/analyzer/lib/src/dart/resolver/typed_literal_resolver.dart
+++ b/pkg/analyzer/lib/src/dart/resolver/typed_literal_resolver.dart
@@ -101,7 +101,7 @@ class TypedLiteralResolver {
     if (typeArguments != null) {
       if (typeArguments.length == 1) {
         DartType elementType = typeArguments[0].typeOrThrow;
-        if (!elementType.isDynamic) {
+        if (elementType is! DynamicType) {
           listType = _typeProvider.listType(elementType);
         }
       }
@@ -220,7 +220,7 @@ class TypedLiteralResolver {
         return iterableType.typeArguments[0];
       }
 
-      if (expressionType.isDynamic) {
+      if (expressionType is DynamicType) {
         return _typeProvider.dynamicType;
       }
 
@@ -411,7 +411,7 @@ class TypedLiteralResolver {
         );
       }
 
-      if (expressionType.isDynamic) {
+      if (expressionType is DynamicType) {
         return _InferredCollectionElementTypeInformation(
           elementType: expressionType,
           keyType: expressionType,
@@ -679,7 +679,7 @@ class TypedLiteralResolver {
     }
     DartType literalType =
         _inferSetOrMapLiteralType(inferrer, literalResolution, node);
-    if (literalType.isDynamic) {
+    if (literalType is DynamicType) {
       // The literal is ambiguous, and further analysis won't resolve the
       // ambiguity.  Leave it as neither a set nor a map.
     } else if (literalType is InterfaceType &&
@@ -821,12 +821,9 @@ class _InferredCollectionElementTypeInformation {
   bool get canBeSet => elementType != null;
 
   bool get isDynamic =>
-      elementType != null &&
-      elementType!.isDynamic &&
-      keyType != null &&
-      keyType!.isDynamic &&
-      valueType != null &&
-      valueType!.isDynamic;
+      elementType is DynamicType &&
+      keyType is DynamicType &&
+      valueType is DynamicType;
 
   bool get mustBeMap => canBeMap && elementType == null;
 
diff --git a/pkg/analyzer/lib/src/error/best_practices_verifier.dart b/pkg/analyzer/lib/src/error/best_practices_verifier.dart
index c410435d46d..346c7925782 100644
--- a/pkg/analyzer/lib/src/error/best_practices_verifier.dart
+++ b/pkg/analyzer/lib/src/error/best_practices_verifier.dart
@@ -629,7 +629,7 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
       // Only report non-aliased, non-user-defined `Null?` and `dynamic?`. Do
       // not report synthetic `dynamic` in place of an unresolved type.
       if ((type is InterfaceType && type.element == _nullType.element ||
-              (type.isDynamic && node.name2.lexeme == 'dynamic')) &&
+              (type is DynamicType && node.name2.lexeme == 'dynamic')) &&
           type.alias == null) {
         _errorReporter.reportErrorForToken(
           WarningCode.UNNECESSARY_QUESTION_MARK,
@@ -753,7 +753,7 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
     }
 
     // `is dynamic` or `is! dynamic`
-    if (rightType.isDynamic) {
+    if (rightType is DynamicType) {
       var rightTypeStr = rightNode.ifTypeOrNull<NamedType>()?.qualifiedName;
       if (rightTypeStr == Keyword.DYNAMIC.lexeme) {
         report();
@@ -1601,12 +1601,12 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
     var rightType = node.type.typeOrThrow;
 
     // `dynamicValue as SomeType` is a valid use case.
-    if (leftType.isDynamic) {
+    if (leftType is DynamicType) {
       return false;
     }
 
     // `x as Unresolved` is already reported as an error.
-    if (rightType.isDynamic) {
+    if (rightType is DynamicType) {
       return false;
     }
 
diff --git a/pkg/analyzer/lib/src/error/literal_element_verifier.dart b/pkg/analyzer/lib/src/error/literal_element_verifier.dart
index 275d9fc05fa..2f32ab60ebd 100644
--- a/pkg/analyzer/lib/src/error/literal_element_verifier.dart
+++ b/pkg/analyzer/lib/src/error/literal_element_verifier.dart
@@ -138,7 +138,7 @@ class LiteralElementVerifier {
   /// assigned to the [elementType] of the enclosing collection.
   void _verifySpreadForListOrSet(bool isNullAware, Expression expression) {
     var expressionType = expression.typeOrThrow;
-    if (expressionType.isDynamic) {
+    if (expressionType is DynamicType) {
       if (typeSystem.strictCasts) {
         return errorReporter.reportErrorForNode(
           CompileTimeErrorCode.NOT_ITERABLE_SPREAD,
@@ -232,7 +232,7 @@ class LiteralElementVerifier {
   /// its key and values are assignable to [mapKeyType] and [mapValueType].
   void _verifySpreadForMap(bool isNullAware, Expression expression) {
     var expressionType = expression.typeOrThrow;
-    if (expressionType.isDynamic) {
+    if (expressionType is DynamicType) {
       if (typeSystem.strictCasts) {
         return errorReporter.reportErrorForNode(
           CompileTimeErrorCode.NOT_MAP_SPREAD,
diff --git a/pkg/analyzer/lib/src/error/return_type_verifier.dart b/pkg/analyzer/lib/src/error/return_type_verifier.dart
index b1d4c40cbab..411d9463d9e 100644
--- a/pkg/analyzer/lib/src/error/return_type_verifier.dart
+++ b/pkg/analyzer/lib/src/error/return_type_verifier.dart
@@ -448,10 +448,10 @@ class ReturnTypeVerifier {
   }
 
   static bool _isVoidDynamic(DartType type) {
-    return type is VoidType || type.isDynamic;
+    return type is VoidType || type is DynamicType;
   }
 
   static bool _isVoidDynamicOrNull(DartType type) {
-    return type is VoidType || type.isDynamic || type.isDartCoreNull;
+    return type is VoidType || type is DynamicType || type.isDartCoreNull;
   }
 }
diff --git a/pkg/analyzer/lib/src/error/type_arguments_verifier.dart b/pkg/analyzer/lib/src/error/type_arguments_verifier.dart
index 63a39b91f4e..f3af78f34c8 100644
--- a/pkg/analyzer/lib/src/error/type_arguments_verifier.dart
+++ b/pkg/analyzer/lib/src/error/type_arguments_verifier.dart
@@ -232,7 +232,7 @@ class TypeArgumentsVerifier {
         declaredType is FunctionType &&
         declaredType.typeFormals.isNotEmpty) {
       List<DartType> typeArgs = node.typeArgumentTypes!;
-      if (typeArgs.any((t) => t.isDynamic)) {
+      if (typeArgs.any((t) => t is DynamicType)) {
         // Issue an error depending on what we're trying to call.
         Expression function = node.function;
         if (function is Identifier) {
@@ -268,7 +268,8 @@ class TypeArgumentsVerifier {
     }
     DartType type = node.typeOrThrow;
     // It's an error if either the key or value was inferred as dynamic.
-    if (type is InterfaceType && type.typeArguments.any((t) => t.isDynamic)) {
+    if (type is InterfaceType &&
+        type.typeArguments.any((t) => t is DynamicType)) {
       // TODO(brianwilkerson) Add StrongModeCode.IMPLICIT_DYNAMIC_SET_LITERAL
       ErrorCode errorCode = node is ListLiteral
           ? LanguageCode.IMPLICIT_DYNAMIC_LIST_LITERAL
@@ -608,7 +609,7 @@ class TypeArgumentsVerifier {
 
     // Check if this type has type arguments and at least one is dynamic.
     // If so, we may need to issue a strict-raw-types error.
-    if (typeArguments.any((t) => t.isDynamic)) {
+    if (typeArguments.any((t) => t is DynamicType)) {
       if (element != null && element.hasOptionalTypeArgs) {
         return false;
       }
diff --git a/pkg/analyzer/lib/src/generated/element_resolver.dart b/pkg/analyzer/lib/src/generated/element_resolver.dart
index 9dcc6de497e..c51ba8ea8fb 100644
--- a/pkg/analyzer/lib/src/generated/element_resolver.dart
+++ b/pkg/analyzer/lib/src/generated/element_resolver.dart
@@ -161,7 +161,7 @@ class ElementResolver {
     if (type == null) {
       return;
     }
-    if (type.isDynamic) {
+    if (type is DynamicType) {
       // Nothing to do.
     } else if (type is InterfaceType) {
       // look up ConstructorElement
diff --git a/pkg/analyzer/lib/src/generated/error_verifier.dart b/pkg/analyzer/lib/src/generated/error_verifier.dart
index 5668ad8edd9..c1cd538d21c 100644
--- a/pkg/analyzer/lib/src/generated/error_verifier.dart
+++ b/pkg/analyzer/lib/src/generated/error_verifier.dart
@@ -825,7 +825,7 @@ class ErrorVerifier extends RecursiveAstVisitor<void>
       if (!_options.implicitDynamic && node.returnType == null) {
         DartType parameterType = node.declaredElement!.type;
         if (parameterType is FunctionType &&
-            parameterType.returnType.isDynamic) {
+            parameterType.returnType is DynamicType) {
           errorReporter.reportErrorForToken(
               LanguageCode.IMPLICIT_DYNAMIC_RETURN,
               node.name,
@@ -2478,7 +2478,7 @@ class ErrorVerifier extends RecursiveAstVisitor<void>
     // Use an explicit string instead of [loopType] to remove the "<E>".
     String loopNamedType = awaitKeyword != null ? 'Stream' : 'Iterable';
 
-    if (iterableType.isDynamic && typeSystem.strictCasts) {
+    if (iterableType is DynamicType && typeSystem.strictCasts) {
       errorReporter.reportErrorForNode(
         CompileTimeErrorCode.FOR_IN_OF_INVALID_TYPE,
         node.iterable,
@@ -3003,7 +3003,7 @@ class ErrorVerifier extends RecursiveAstVisitor<void>
     if (_options.implicitDynamic) {
       return;
     }
-    if (variable.hasImplicitType && variable.type.isDynamic) {
+    if (variable.hasImplicitType && variable.type is DynamicType) {
       ErrorCode errorCode;
       if (variable is FieldElement) {
         errorCode = LanguageCode.IMPLICIT_DYNAMIC_FIELD;
@@ -3026,7 +3026,7 @@ class ErrorVerifier extends RecursiveAstVisitor<void>
     if (element is PropertyAccessorElement && element.isSetter) {
       return;
     }
-    if (element.hasImplicitReturnType && element.returnType.isDynamic) {
+    if (element.hasImplicitReturnType && element.returnType is DynamicType) {
       errorReporter.reportErrorForToken(LanguageCode.IMPLICIT_DYNAMIC_RETURN,
           functionName, [element.displayName]);
     }
@@ -3041,7 +3041,7 @@ class ErrorVerifier extends RecursiveAstVisitor<void>
     DartType type = node.typeOrThrow;
     if (type is ParameterizedType &&
         type.typeArguments.isNotEmpty &&
-        type.typeArguments.any((t) => t.isDynamic)) {
+        type.typeArguments.any((t) => t is DynamicType)) {
       errorReporter
           .reportErrorForNode(LanguageCode.IMPLICIT_DYNAMIC_TYPE, node, [type]);
     }
diff --git a/pkg/analyzer/lib/src/generated/resolver.dart b/pkg/analyzer/lib/src/generated/resolver.dart
index 8c9957854c1..e26d46ee901 100644
--- a/pkg/analyzer/lib/src/generated/resolver.dart
+++ b/pkg/analyzer/lib/src/generated/resolver.dart
@@ -629,8 +629,9 @@ class ResolverVisitor extends ThrowingAstVisitor<void>
         errorCode = CompileTimeErrorCode.BODY_MIGHT_COMPLETE_NORMALLY;
       } else {
         var returnTypeBase = typeSystem.futureOrBase(returnType);
-        if (returnTypeBase is VoidType ||
-            returnTypeBase.isDynamic ||
+        if (returnTypeBase is DynamicType ||
+            returnTypeBase is UnknownInferredType ||
+            returnTypeBase is VoidType ||
             returnTypeBase.isDartCoreNull) {
           return;
         } else {
@@ -2214,7 +2215,7 @@ class ResolverVisitor extends ThrowingAstVisitor<void>
       node.parameters.accept(this);
       node.initializers.accept(this);
       node.redirectedConstructor?.accept(this);
-      node.body.resolve(this, returnType.isDynamic ? null : returnType);
+      node.body.resolve(this, returnType is DynamicType ? null : returnType);
       elementResolver.visitConstructorDeclaration(node);
     } finally {
       _enclosingFunction = outerFunction;
@@ -2957,7 +2958,7 @@ class ResolverVisitor extends ThrowingAstVisitor<void>
       node.returnType?.accept(this);
       node.typeParameters?.accept(this);
       node.parameters?.accept(this);
-      node.body.resolve(this, returnType.isDynamic ? null : returnType);
+      node.body.resolve(this, returnType is DynamicType ? null : returnType);
       elementResolver.visitMethodDeclaration(node);
     } finally {
       _enclosingFunction = outerFunction;
@@ -3653,8 +3654,9 @@ class ResolverVisitor extends ThrowingAstVisitor<void>
         final targetFutureType = instanceOfFuture.typeArguments.first;
         final expectedReturnType = typeProvider.futureOrType(targetFutureType);
         final returnTypeBase = typeSystem.futureOrBase(expectedReturnType);
-        if (returnTypeBase is VoidType ||
-            returnTypeBase.isDynamic ||
+        if (returnTypeBase is DynamicType ||
+            returnTypeBase is UnknownInferredType ||
+            returnTypeBase is VoidType ||
             returnTypeBase.isDartCoreNull) {
           return;
         }
diff --git a/pkg/analyzer/lib/src/task/strong/checker.dart b/pkg/analyzer/lib/src/task/strong/checker.dart
index 98ba14bd803..bc6acc79c2d 100644
--- a/pkg/analyzer/lib/src/task/strong/checker.dart
+++ b/pkg/analyzer/lib/src/task/strong/checker.dart
@@ -594,7 +594,7 @@ class CodeChecker extends RecursiveAstVisitor {
       }
     }
     if (yieldStar) {
-      if (type.isDynamic) {
+      if (type is DynamicType) {
         // Ensure it's at least a Stream / Iterable.
         return expectedElement.instantiate(
           typeArguments: [_typeProvider.dynamicType],
@@ -606,7 +606,7 @@ class CodeChecker extends RecursiveAstVisitor {
         return type;
       }
     }
-    if (type.isDynamic) {
+    if (type is DynamicType) {
       return type;
     } else if (type is InterfaceType && type.element == expectedElement) {
       return type.typeArguments[0];
diff --git a/pkg/analyzer/pubspec.yaml b/pkg/analyzer/pubspec.yaml
index d12c9c2a934..fa3aa667497 100644
--- a/pkg/analyzer/pubspec.yaml
+++ b/pkg/analyzer/pubspec.yaml
@@ -1,5 +1,5 @@
 name: analyzer
-version: 5.11.1
+version: 5.12.0-dev
 description: >-
   This package provides a library that performs static analysis of Dart code.
 repository: https://github.com/dart-lang/sdk/tree/main/pkg/analyzer
diff --git a/pkg/analyzer/test/generated/resolver_test_case.dart b/pkg/analyzer/test/generated/resolver_test_case.dart
index 64edff5c9c4..7e0111bd166 100644
--- a/pkg/analyzer/test/generated/resolver_test_case.dart
+++ b/pkg/analyzer/test/generated/resolver_test_case.dart
@@ -70,7 +70,7 @@ class ResolutionVerifier extends RecursiveAstVisitor<void> {
       return;
     }
     var operandType = node.leftOperand.staticType;
-    if (operandType == null || operandType.isDynamic) {
+    if (operandType == null || operandType is DynamicType) {
       return;
     }
     _checkResolved(node, node.staticElement, (node) => node is MethodElement);
@@ -124,7 +124,7 @@ class ResolutionVerifier extends RecursiveAstVisitor<void> {
   void visitIndexExpression(IndexExpression node) {
     node.visitChildren(this);
     var targetType = node.realTarget.staticType;
-    if (targetType == null || targetType.isDynamic) {
+    if (targetType == null || targetType is DynamicType) {
       return;
     }
     var parent = node.parent;
@@ -162,7 +162,7 @@ class ResolutionVerifier extends RecursiveAstVisitor<void> {
       return;
     }
     var operandType = node.operand.staticType;
-    if (operandType == null || operandType.isDynamic) {
+    if (operandType == null || operandType is DynamicType) {
       return;
     }
     _checkResolved(node, node.staticElement, (node) => node is MethodElement);
@@ -173,7 +173,7 @@ class ResolutionVerifier extends RecursiveAstVisitor<void> {
     SimpleIdentifier prefix = node.prefix;
     prefix.accept(this);
     var prefixType = prefix.staticType;
-    if (prefixType == null || prefixType.isDynamic) {
+    if (prefixType == null || prefixType is DynamicType) {
       return;
     }
     _checkResolved(node, node.staticElement, null);
@@ -186,7 +186,7 @@ class ResolutionVerifier extends RecursiveAstVisitor<void> {
       return;
     }
     var operandType = node.operand.staticType;
-    if (operandType == null || operandType.isDynamic) {
+    if (operandType == null || operandType is DynamicType) {
       return;
     }
     _checkResolved(node, node.staticElement, (node) => node is MethodElement);
@@ -197,7 +197,7 @@ class ResolutionVerifier extends RecursiveAstVisitor<void> {
     Expression target = node.realTarget;
     target.accept(this);
     var targetType = target.staticType;
-    if (targetType == null || targetType.isDynamic) {
+    if (targetType == null || targetType is DynamicType) {
       return;
     }
     var parent = node.parent;
@@ -218,9 +218,7 @@ class ResolutionVerifier extends RecursiveAstVisitor<void> {
     }
 
     var staticType = node.staticType;
-    if (staticType != null &&
-        staticType.isDynamic &&
-        node.staticElement == null) {
+    if (staticType is DynamicType && node.staticElement == null) {
       return;
     }
 
@@ -233,7 +231,7 @@ class ResolutionVerifier extends RecursiveAstVisitor<void> {
       if (identical(invocation.methodName, node)) {
         var target = invocation.realTarget;
         var targetType = target?.staticType;
-        if (targetType == null || targetType.isDynamic) {
+        if (targetType == null || targetType is DynamicType) {
           return;
         }
       }
diff --git a/pkg/analyzer_plugin/lib/src/utilities/change_builder/change_builder_dart.dart b/pkg/analyzer_plugin/lib/src/utilities/change_builder/change_builder_dart.dart
index b6b12dfd675..4a33deb8af9 100644
--- a/pkg/analyzer_plugin/lib/src/utilities/change_builder/change_builder_dart.dart
+++ b/pkg/analyzer_plugin/lib/src/utilities/change_builder/change_builder_dart.dart
@@ -69,7 +69,7 @@ class DartEditBuilderImpl extends EditBuilderImpl implements DartEditBuilder {
 
   @override
   bool canWriteType(DartType? type, {ExecutableElement? methodBeingCopied}) =>
-      type != null && !type.isDynamic
+      type != null && type is! DynamicType
           ? _canWriteType(type, methodBeingCopied: methodBeingCopied)
           : false;
 
@@ -273,7 +273,7 @@ class DartEditBuilderImpl extends EditBuilderImpl implements DartEditBuilder {
       write(Keyword.STATIC.lexeme);
       write(' ');
     }
-    if (returnType != null && !returnType.isDynamic) {
+    if (returnType != null && returnType is! DynamicType) {
       if (writeType(returnType, groupName: returnTypeGroupName)) {
         write(' ');
       }
@@ -730,7 +730,7 @@ class DartEditBuilderImpl extends EditBuilderImpl implements DartEditBuilder {
       write(name);
     }
     write('(');
-    if (parameterType != null && !parameterType.isDynamic) {
+    if (parameterType != null && parameterType is! DynamicType) {
       if (writeType(parameterType, groupName: parameterTypeGroupName)) {
         write(' ');
       }
@@ -753,7 +753,7 @@ class DartEditBuilderImpl extends EditBuilderImpl implements DartEditBuilder {
       ExecutableElement? methodBeingCopied,
       bool required = false}) {
     var wroteType = false;
-    if (type != null && !type.isDynamic) {
+    if (type != null && type is! DynamicType) {
       if (groupName != null) {
         addLinkedEdit(groupName, (LinkedEditBuilder builder) {
           wroteType = _writeType(type, methodBeingCopied: methodBeingCopied);
@@ -879,7 +879,7 @@ class DartEditBuilderImpl extends EditBuilderImpl implements DartEditBuilder {
     if (type == null) {
       return false;
     }
-    if (type.isDynamic) {
+    if (type is DynamicType) {
       if (required) {
         return true;
       }
@@ -1092,7 +1092,7 @@ class DartEditBuilderImpl extends EditBuilderImpl implements DartEditBuilder {
       }
     }
     // use type
-    if (expectedType != null && !expectedType.isDynamic) {
+    if (expectedType != null && expectedType is! DynamicType) {
       if (expectedType.isDartCoreInt) {
         _addSingleCharacterName(excluded, res, $i);
       } else if (expectedType.isDartCoreDouble) {
@@ -1223,7 +1223,7 @@ class DartEditBuilderImpl extends EditBuilderImpl implements DartEditBuilder {
     if (type == null) {
       return false;
     }
-    if (type.isDynamic) {
+    if (type is DynamicType) {
       if (required) {
         write('dynamic');
         return true;
@@ -1360,7 +1360,7 @@ class DartEditBuilderImpl extends EditBuilderImpl implements DartEditBuilder {
       var hasArguments = false;
       var allArgumentsVisible = true;
       for (var argument in typeArguments) {
-        hasArguments = hasArguments || !argument.isDynamic;
+        hasArguments = hasArguments || argument is! DynamicType;
         allArgumentsVisible = allArgumentsVisible &&
             _getVisibleType(argument, methodBeingCopied: methodBeingCopied) !=
                 null;
@@ -1628,7 +1628,7 @@ class DartFileEditBuilderImpl extends FileEditBuilderImpl
     // Check whether the type needs to be replaced.
     //
     var type = typeAnnotation?.type;
-    if (type == null || type.isDynamic || type.isDartAsyncFuture) {
+    if (type == null || type is DynamicType || type.isDartAsyncFuture) {
       return;
     }
 
diff --git a/pkg/analyzer_plugin/lib/utilities/completion/type_member_contributor.dart b/pkg/analyzer_plugin/lib/utilities/completion/type_member_contributor.dart
index 821bea82386..264ce1c1dbf 100644
--- a/pkg/analyzer_plugin/lib/utilities/completion/type_member_contributor.dart
+++ b/pkg/analyzer_plugin/lib/utilities/completion/type_member_contributor.dart
@@ -75,7 +75,7 @@ class TypeMemberContributor implements CompletionContributor {
 
     // Determine the target expression's type
     var type = expression.staticType;
-    if (type == null || type.isDynamic) {
+    if (type == null || type is DynamicType) {
       // If the expression does not provide a good type
       // then attempt to get a better type from the element
       if (expression is Identifier) {
@@ -87,7 +87,7 @@ class TypeMemberContributor implements CompletionContributor {
         } else if (elem is LocalVariableElement) {
           type = elem.type;
         }
-        if ((type == null || type.isDynamic) &&
+        if ((type == null || type is DynamicType) &&
             expression is SimpleIdentifier) {
           // If the element does not provide a good type
           // then attempt to get a better type from a local declaration
@@ -111,7 +111,7 @@ class TypeMemberContributor implements CompletionContributor {
         containingMethodName = id.lexeme;
       }
     }
-    if (type == null || type.isDynamic) {
+    if (type == null || type is DynamicType) {
       // Suggest members from object if target is "dynamic"
       type = request.result.typeProvider.objectType;
     }
diff --git a/pkg/nnbd_migration/lib/src/already_migrated_code_decorator.dart b/pkg/nnbd_migration/lib/src/already_migrated_code_decorator.dart
index cc58f759586..6a357ab5141 100644
--- a/pkg/nnbd_migration/lib/src/already_migrated_code_decorator.dart
+++ b/pkg/nnbd_migration/lib/src/already_migrated_code_decorator.dart
@@ -29,7 +29,7 @@ class AlreadyMigratedCodeDecorator {
   /// TODO(paulberry): do we still need element or can we use target now?
   DecoratedType decorate(
       DartType type, Element element, NullabilityNodeTarget target) {
-    if (type is VoidType || type.isDynamic) {
+    if (type is VoidType || type is DynamicType) {
       var node = NullabilityNode.forAlreadyMigrated(target);
       _graph.makeNullableUnion(
           node, AlwaysNullableTypeOrigin.forElement(element, type is VoidType));
diff --git a/pkg/nnbd_migration/lib/src/decorated_type.dart b/pkg/nnbd_migration/lib/src/decorated_type.dart
index 40ec33e1fa9..35fe682ec39 100644
--- a/pkg/nnbd_migration/lib/src/decorated_type.dart
+++ b/pkg/nnbd_migration/lib/src/decorated_type.dart
@@ -450,7 +450,7 @@ class DecoratedType implements DecoratedTypeInfo, SubstitutedType {
       } else {
         return inner._performSubstitution(this, undecoratedResult!);
       }
-    } else if (type is VoidType || type!.isDynamic) {
+    } else if (type is VoidType || type is DynamicType) {
       return this;
     }
     throw '$type.substitute($type | $substitution)'; // TODO(paulberry)
diff --git a/pkg/nnbd_migration/lib/src/edge_builder.dart b/pkg/nnbd_migration/lib/src/edge_builder.dart
index 1785cf5ef6f..a4f4b8eebb4 100644
--- a/pkg/nnbd_migration/lib/src/edge_builder.dart
+++ b/pkg/nnbd_migration/lib/src/edge_builder.dart
@@ -2275,7 +2275,7 @@ class EdgeBuilder extends GeneralizingAstVisitor<DecoratedType>
         ? NullabilityNode.forLUB(left.node, right.node)
         : _nullabilityNodeForGLB(astNode, left.node, right.node);
 
-    if (type!.isDynamic || type is VoidType) {
+    if (type is DynamicType || type is VoidType) {
       return DecoratedType(type, node);
     } else if (leftType!.isBottom) {
       return right.withNode(node);
@@ -3439,7 +3439,7 @@ class EdgeBuilder extends GeneralizingAstVisitor<DecoratedType>
 
   EdgeOrigin _makeEdgeOrigin(DecoratedType sourceType, Expression expression,
       {bool isSetupAssignment = false}) {
-    if (sourceType.type!.isDynamic) {
+    if (sourceType.type is DynamicType) {
       return DynamicAssignmentOrigin(source, expression,
           isSetupAssignment: isSetupAssignment);
     } else {
@@ -3913,7 +3913,7 @@ mixin _AssignmentChecker {
             hard: false);
         return;
       }
-    } else if (destinationType.isDynamic ||
+    } else if (destinationType is DynamicType ||
         destinationType is VoidType ||
         destinationType.isDartCoreObject) {
       // No further edges need to be created, since all types are trivially
@@ -3965,7 +3965,7 @@ mixin _AssignmentChecker {
             hard: false,
             checkable: false);
       }
-    } else if (destinationType.isDynamic || sourceType.isDynamic) {
+    } else if (destinationType is DynamicType || sourceType is DynamicType) {
       // ok; nothing further to do.
     } else if (destinationType is InterfaceType && sourceType is FunctionType) {
       // Either this is an upcast to Function or Object, or it is erroneous
@@ -3986,7 +3986,7 @@ mixin _AssignmentChecker {
     _connect(source.node, destination.node, origin, FixReasonTarget.root,
         hard: hard);
 
-    if (sourceType.isDynamic ||
+    if (sourceType is DynamicType ||
         sourceType.isDartCoreObject ||
         sourceType is VoidType) {
       if (destinationType is InterfaceType) {
diff --git a/pkg/nnbd_migration/lib/src/fix_aggregator.dart b/pkg/nnbd_migration/lib/src/fix_aggregator.dart
index 31609d64933..e3f27431e76 100644
--- a/pkg/nnbd_migration/lib/src/fix_aggregator.dart
+++ b/pkg/nnbd_migration/lib/src/fix_aggregator.dart
@@ -120,7 +120,7 @@ class FixAggregator extends UnifyingAstVisitor<void> {
   String typeFormalToCode(TypeParameterElement formal) {
     var bound = formal.bound;
     if (bound == null ||
-        bound.isDynamic ||
+        bound is DynamicType ||
         (bound.isDartCoreObject &&
             bound.nullabilitySuffix != NullabilitySuffix.none)) {
       return formal.name;
diff --git a/pkg/nnbd_migration/lib/src/fix_builder.dart b/pkg/nnbd_migration/lib/src/fix_builder.dart
index ec93c55c09f..e8b9da77441 100644
--- a/pkg/nnbd_migration/lib/src/fix_builder.dart
+++ b/pkg/nnbd_migration/lib/src/fix_builder.dart
@@ -472,7 +472,7 @@ class MigrationResolutionHooksImpl
         .decoratedTypeParameterBound(element, allowNullUnparentedBounds: true);
     if (decoratedBound == null) return element.boundInternal;
     var bound = _fixBuilder._variables!.toFinalType(decoratedBound);
-    if (bound.isDynamic) {
+    if (bound is DynamicType) {
       return null;
     } else if (bound.isDartCoreObject &&
         bound.nullabilitySuffix == NullabilitySuffix.question) {
@@ -807,7 +807,7 @@ class MigrationResolutionHooksImpl
               hintComment: hint),
           hint: hint);
     }
-    if (type.isDynamic) return type;
+    if (type is DynamicType) return type;
     var ancestor = _findNullabilityContextAncestor(node);
     context ??= _contextTypes[ancestor] ?? DynamicTypeImpl.instance;
     if (!_isSubtypeOrCoercible(type, context)) {
@@ -1082,7 +1082,7 @@ abstract class _AssignmentLikeExpressionHandler {
               .isWeakNullAware = true;
         }
       } else {
-        if (!readType!.isDynamic &&
+        if (readType is! DynamicType &&
             fixBuilder._typeSystem.isPotentiallyNullable(readType!)) {
           (fixBuilder._getChange(node) as NodeChangeForAssignmentLike)
               .hasNullableSource = true;
@@ -1460,7 +1460,7 @@ class _FixBuilderPreVisitor extends GeneralizingAstVisitor<void>
   }
 
   bool _typeIsNaturallyNullable(DartType type) =>
-      type.isDynamic || type is VoidType || type.isDartCoreNull;
+      type is DynamicType || type is VoidType || type.isDartCoreNull;
 }
 
 /// Specialization of [_AssignmentLikeExpressionHandler] for
diff --git a/pkg/nnbd_migration/lib/src/node_builder.dart b/pkg/nnbd_migration/lib/src/node_builder.dart
index 3d8f3107aca..3443226d607 100644
--- a/pkg/nnbd_migration/lib/src/node_builder.dart
+++ b/pkg/nnbd_migration/lib/src/node_builder.dart
@@ -531,7 +531,7 @@ class NodeBuilder extends GeneralizingAstVisitor<DecoratedType>
   DecoratedType visitTypeAnnotation(TypeAnnotation node) {
     var type = node.type!;
     var target = safeTarget.withCodeRef(node);
-    if (type is VoidType || type.isDynamic) {
+    if (type is VoidType || type is DynamicType) {
       var nullabilityNode = NullabilityNode.forTypeAnnotation(target);
       var decoratedType = DecoratedType(type, nullabilityNode);
       _variables.recordDecoratedTypeAnnotation(source, node, decoratedType);
@@ -777,7 +777,7 @@ class NodeBuilder extends GeneralizingAstVisitor<DecoratedType>
         decoratedReturnType = DecoratedType.forImplicitType(
             _typeProvider, functionType.returnType, _graph, target);
         instrumentation?.implicitReturnType(source, node, decoratedReturnType);
-        if (isExternal && functionType.returnType.isDynamic) {
+        if (isExternal && functionType.returnType is DynamicType) {
           _graph.makeNullableUnion(
               decoratedReturnType.node, ExternalDynamicOrigin(source, node));
         }
diff --git a/pkg/nnbd_migration/lib/src/variables.dart b/pkg/nnbd_migration/lib/src/variables.dart
index 3a62643af40..dbe9f4bce58 100644
--- a/pkg/nnbd_migration/lib/src/variables.dart
+++ b/pkg/nnbd_migration/lib/src/variables.dart
@@ -297,7 +297,7 @@ class Variables {
   /// types should be nullable and which types should not.
   DartType toFinalType(DecoratedType decoratedType) {
     var type = decoratedType.type!;
-    if (type is VoidType || type.isDynamic) return type;
+    if (type is VoidType || type is DynamicType) return type;
     if (type is NeverType) {
       if (decoratedType.node.isNullable) {
         return (_typeProvider.nullType as TypeImpl)
diff --git a/pkg/nnbd_migration/test/node_builder_test.dart b/pkg/nnbd_migration/test/node_builder_test.dart
index 7fc1668e911..12f2090865d 100644
--- a/pkg/nnbd_migration/test/node_builder_test.dart
+++ b/pkg/nnbd_migration/test/node_builder_test.dart
@@ -1084,7 +1084,7 @@ typedef F();
 ''');
     var decoratedType = variables
         .decoratedElementType(findElement.typeAlias('F').aliasedElement!);
-    expect(decoratedType.returnType!.type!.isDynamic, isTrue);
+    expect(decoratedType.returnType!.type is DynamicType, isTrue);
     expect(decoratedType.returnType!.node.isImmutable, false);
     expect(decoratedType.typeFormals, isEmpty);
   }
@@ -1347,7 +1347,7 @@ typedef F = Function();
         .decoratedElementType(findElement.typeAlias('F').aliasedElement!);
     expect(decoratedType,
         same(decoratedGenericFunctionTypeAnnotation('Function')));
-    expect(decoratedType.returnType!.type!.isDynamic, isTrue);
+    expect(decoratedType.returnType!.type is DynamicType, isTrue);
     expect(decoratedType.returnType!.node.isImmutable, false);
     expect(decoratedType.typeFormals, isEmpty);
   }
@@ -1808,7 +1808,7 @@ void f(x) {}
         findNode.simpleFormalParameter('x').declaredElement!);
     expect(decoratedFunctionType('f').positionalParameters![0],
         same(decoratedType));
-    expect(decoratedType.type!.isDynamic, isTrue);
+    expect(decoratedType.type is DynamicType, isTrue);
   }
 
   Future<void> test_topLevelFunction_parameterType_named_no_default() async {
@@ -1897,7 +1897,7 @@ void f(int i) {}
 f() {}
 ''');
     var decoratedType = decoratedFunctionType('f').returnType!;
-    expect(decoratedType.type!.isDynamic, isTrue);
+    expect(decoratedType.type is DynamicType, isTrue);
   }
 
   Future<void> test_topLevelFunction_returnType_simple() async {