Mastering TypeScript Utility Types: Partial, Pick, Omit, Record & More

[Lomanu4]

TypeScript utility types are powerful tools that help developers write cleaner, more maintainable, and type-safe code. Whether you’re building frontend apps with React or backend APIs with Node.js, utility types let you transform and manipulate types without rewriting logic.

? Watch the full tutorial video here:

.

? What You'll Learn


This video and blog cover the most commonly used TypeScript utility types:

• Partial<T>
• Pick<T, K>
• Omit<T, K>
• Record<K, T>
• Readonly<T>
• Required<T>

Partial<T>


Makes all properties in a type optional.


interface User {
id: number;
name: string;
email: string;
}

const updateUser = (id: number, updates: Partial<User>) => {
// updates can include one or more fields
};

Useful for update forms or PATCH requests.

Pick<T, K>


Creates a new type by picking a subset of properties.


interface User {
id: number;
name: string;
email: string;
}

type UserPreview = Pick<User, "id" | "name">;

const preview: UserPreview = {
id: 1,
name: "Jane",
};

Great for displaying minimal data in components or lists.

Omit<T, K>


Creates a new type by omitting specific properties.


interface User {
id: number;
name: string;
email: string;
}

type UserWithoutEmail = Omit<User, "email">;

const user: UserWithoutEmail = {
id: 1,
name: "John",
};

Ideal when hiding sensitive fields (e.g., passwords, emails).

Record<K, T>


Creates an object type with keys of type K and values of type T.


type Roles = "admin" | "user" | "guest";

const permissions: Record<Roles, boolean> = {
admin: true,
user: true,
guest: false,
};

Useful for enums, permission sets, or configuration maps.

Readonly<T>


Makes all properties in a type immutable.


interface Settings {
theme: string;
darkMode: boolean;
}

const config: Readonly<Settings> = {
theme: "light",
darkMode: false,
};

config.theme = "dark"; // Error: Cannot assign to 'theme'

Prevents accidental mutations.

Required<T>


Makes all optional properties required.


interface Profile {
username?: string;
bio?: string;
}

type CompleteProfile = Required<Profile>;

const user: CompleteProfile = {
username: "samnjoku",
bio: "Dev Advocate",
};

Useful when ensuring that an object is fully populated before sending.

? Watch & Share

?

Пожалуйста Авторизируйтесь или Зарегистрируйтесь для просмотра скрытого текста.

and get hands-on with real-world examples.

If you found the content helpful, please like, comment, and subscribe to support the channel!

? Bonus Tip


You can combine utility types like this:


type EditableUser = Partial<Omit<User, "id">>;

This makes all properties except id optional.

Thanks for reading and watching!
Let me know in the comments: Which TypeScript utility type do you use the most?

Пожалуйста Авторизируйтесь или Зарегистрируйтесь для просмотра скрытого текста.