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Advanced Types

Utility Types — Pick, Omit, Exclude, Extract, NonNullable, ReturnType, Parameters

Master TypeScript's standard built-in Utility Types: Pick, Omit, Exclude, Extract, NonNullable, ReturnType, and Parameters.

Last Updated: July 29, 2026 10 min read

TypeScript provides built-in global Utility Types to perform common type transformations on objects, unions, and functions.

1. Object Transformation Utilities

1. Pick

Constructs a type by selecting a set of properties K from object T.

2. Omit

Constructs a type by removing properties K from object T.

2. Union Transformation Utilities

1. Exclude

Excludes members from a union type.

2. Extract

Extracts members from a union type that match specified types.

3. NonNullable

Removes null and undefined from type T.

3. Function Type Utilities

1. ReturnType

Extracts the return type of a function type T.

2. Parameters

Extracts the parameter types of a function type T as a Tuple.

4. Interactive Code Playground

Test utility types below:

5. Summary Cheat Sheet Table

Utility TypeTargetPurpose
PickObjectKeeps only keys K from T
OmitObjectRemoves keys K from T
ExcludeUnionRemoves U arms from union T
ExtractUnionKeeps U arms from union T
NonNullableAnyStrips null and undefined
ReturnTypeFunctionExtracts function return type
| Parameters | Function | Extracts parameter tuple |