TypeScript Utility Types – Complete List with Examples

Utility types transform other types, so you describe a shape once and derive the rest. They exist only at compile time: they don't change your JavaScript output. Lines marked // @ts-expect-error show what the compiler rejects.

Name	Description	Since
`Partial<Type>`	Make every property of a type optional. Useful for update functions that accept only the fields that change.	2.1
`Required<Type>`	Make every property of a type required, removing the ? from optional properties. The opposite of Partial.	2.1
`Readonly<Type>`	Make every property of a type read-only, so the compiler rejects assignments to them after creation.	2.1
`Pick<Type, Keys>`	Build a type from just some properties of another type. Handy for API responses and props that need a subset.	2.1
`Omit<Type, Keys>`	Build a type with all properties of another type except the ones you list. The opposite of Pick.	3.5
`Record<Keys, Type>`	Build an object type whose keys come from Keys and whose values all have Type. Great for lookup tables.	2.1
`Exclude<UnionType, ExcludedMembers>`	Remove members from a union type. Exclude<'a' \| 'b' \| 'c', 'a'> is 'b' \| 'c'.	2.8
`Extract<Type, Union>`	Keep only the members of a union that are assignable to another type. The opposite of Exclude.	2.8
`NonNullable<Type>`	Remove null and undefined from a type, for values you've already checked or that can never be missing.	2.8
`ReturnType<Type>`	Get the return type of a function type, so other code can reuse it without repeating it.	2.8
`Parameters<Type>`	Get a function's parameter types as a tuple, useful for wrappers that pass arguments through.	3.1
`Awaited<Type>`	Unwrap the value type of a Promise (recursively), like what await gives you. Awaited<Promise<number>> is number.	4.5
`InstanceType<Type>`	Get the type of the object a class constructor creates, from the constructor's type.	2.8
`NoInfer<Type>`	Stop TypeScript from inferring a type parameter from a particular argument, so other arguments decide it.	5.4
`Uppercase<StringType>`	Turn a string literal type into upper case at the type level: Uppercase<'get'> is 'GET'.	4.1
`Capitalize<StringType>`	Upper-case the first character of a string literal type: Capitalize<'click'> is 'Click'. Used to build names like onClick.	4.1

Name

Description

Since

Partial<Type>

Make every property of a type optional. Useful for update functions that accept only the fields that change.

2.1

Required<Type>

Make every property of a type required, removing the ? from optional properties. The opposite of Partial.

2.1

Readonly<Type>

Make every property of a type read-only, so the compiler rejects assignments to them after creation.

2.1

Pick<Type, Keys>

Build a type from just some properties of another type. Handy for API responses and props that need a subset.

2.1

Omit<Type, Keys>

Build a type with all properties of another type except the ones you list. The opposite of Pick.

3.5

Record<Keys, Type>

Build an object type whose keys come from Keys and whose values all have Type. Great for lookup tables.

2.1

Exclude<UnionType, ExcludedMembers>

Remove members from a union type. Exclude<'a' | 'b' | 'c', 'a'> is 'b' | 'c'.

2.8

Extract<Type, Union>

Keep only the members of a union that are assignable to another type. The opposite of Exclude.

2.8

NonNullable<Type>

Remove null and undefined from a type, for values you've already checked or that can never be missing.

2.8

ReturnType<Type>

Get the return type of a function type, so other code can reuse it without repeating it.

2.8

Parameters<Type>

Get a function's parameter types as a tuple, useful for wrappers that pass arguments through.

3.1

Awaited<Type>

Unwrap the value type of a Promise (recursively), like what await gives you. Awaited<Promise<number>> is number.

4.5

InstanceType<Type>

Get the type of the object a class constructor creates, from the constructor's type.

2.8

NoInfer<Type>

Stop TypeScript from inferring a type parameter from a particular argument, so other arguments decide it.

5.4

Uppercase<StringType>

Turn a string literal type into upper case at the type level: Uppercase<'get'> is 'GET'.

4.1

Capitalize<StringType>

Upper-case the first character of a string literal type: Capitalize<'click'> is 'Click'. Used to build names like onClick.

4.1