JSON to TypeScript

Paste any JSON and get TypeScript interfaces instantly. Handles nested objects, arrays, and union types — all generated client-side with zero data sent to any server.

Open JSON to TypeScript

Features

Accurate Types

Infers string, number, boolean, arrays, and nested objects.

Nested Interfaces

Generates separate interfaces for every nested object.

Instant Generation

Types appear as soon as you click — no waiting.

Fully Private

Your JSON data is processed locally in your browser.

Frequently Asked Questions

How does JSON to TypeScript conversion work?

The tool analyzes your JSON data structure and infers TypeScript types for each field. Objects become interfaces, arrays get typed based on their contents, and primitive values map to string, number, or boolean. Nested objects generate separate interfaces automatically.

Does it handle arrays of different types?

Yes. If an array contains mixed types (e.g., strings and numbers), the tool generates a union type. For arrays of objects, it merges all objects to capture every possible field and creates a comprehensive interface.

Can I customize the generated interface name?

Yes! Enter your preferred root interface name in the text field above the editor. Nested interfaces are named based on their JSON key names, keeping the output clean and meaningful.

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