🔷 TypeScript Utility Types Generator

What can TypeScript Utility Types Generator do?

TypeScript Utility Types Generator is a free online developer tool that automatically generates expanded results for all common utility types from a TypeScript interface definition. It supports Partial, Required, Readonly, Pick, Omit, Record, ReturnType, Parameters, and more — visually showing property changes for each transformation. Ideal for TypeScript learning, type design, and code refactoring. All processing happens locally in your browser.

Core Features

• Partial: Make all properties optional
• Required: Make all optional properties required
• Readonly: Make all properties read-only
• Pick: Select a subset of specified properties
• Omit: Exclude specified properties
• Record: Generate key-value mapping type

How to Use

1. Enter a TypeScript interface definition in the input box.

2. For Pick/Omit, enter property names in the keys field (comma-separated).

3. Click "Generate Types" to see all transformation results.

4. Click "Copy All" or "Download TS" to get the code.

Use Cases

Case 1: API Type Design

Use Partial for update interfaces (fields optional), Required for create interfaces (fields required).

Case 2: Form Types

Use Partial for form initial values (all fields optional), then Required for submission validation.

Case 3: Learning TypeScript

Visually compare original types with utility type results to understand type transformations.

Extended Knowledge

TypeScript Utility Types are built-in type transformation tools. Partial uses keyof T to iterate all keys and add ? modifiers. Required removes ? with -?. Readonly adds readonly. Pick filters keys with K & keyof T. Omit equals Pick>. Record equals {[key in K]:V}. Advanced utility types include Exclude/Extract/NonNullable/ReturnType/Parameters/InstanceType.