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TypeScript

TypeScript Intersection Types

Intersection types smash multiple custom types into a single type.

Read Time

5 min read

Difficulty

Beginner

Last Updated

Jun 15, 2026

Version

v1.0.0

Introduction

While a Union type is an "OR" statement, an Intersection type is an "AND" statement. It combines two completely separate interfaces or types together. The final variable must contain every single property from both original types.

Example

1/* this combines types */
2interface ErrorHandling {
3  success: boolean;
4  error?: string;
5}
6
7interface ArtworksData {
8  artworks: { title: string }[];
9}
10
11type ArtworksResponse = ArtworksData & ErrorHandling;

Key Points

Use the ampersand symbol `&` to create an intersection.
It means "this AND that".
It is commonly used when combining data from multiple API responses.
If a property is missing, TypeScript throws an error.

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