Sometimes, we want to get a function’s return value type with TypeScript.

In this article, we’ll look at how to get a function’s return value type with TypeScript.

How to get a function’s return value type with TypeScript?

To get a function’s return value type with TypeScript, we can use the ReturnType type.

For instance, we write

const createPerson = () => ({
  firstName: "John",
  lastName: "Doe",
});

type Person = ReturnType<typeof createPerson>;

to get the type of the createPerson function with typeof createPerson.

Then we can get the return type of the function with ReturnType<typeof createPerson> and assign the type to the Person alias.

Conclusion

To get a function’s return value type with TypeScript, we can use the ReturnType type.