JSON → TypeScript

FreePrivateInstant

Generate TypeScript interfaces or types instantly from JSON data. Great for React, Next.js, APIs, forms, and strongly typed frontend apps. Runs privately in your browser.

  • Create interfaces in one click
  • Better autocomplete & type safety
  • Great for API responses
  • No upload required
JSON input

Paste JSON object or array to generate types.

Generated TypeScript
Ctrl+Enter Generate

JSON to TypeScript Interface Generator

Convert JSON data into TypeScript interfaces instantly. Save time, improve autocomplete, and build safer frontend applications with generated types for APIs, forms, configs, and more.

Why This Matters

Faster Development
Skip manual interface writing.
Better Autocomplete
Improve editor hints and DX.
Safer APIs
Catch shape mismatches earlier.
Frontend Ready
Perfect for React, Next.js, and TypeScript apps.

How to Use

  1. Paste JSON data.
  2. Set root interface name.
  3. Click Generate or press Ctrl+Enter.
  4. Review types.
  5. Copy or download types.ts.

Features

  • Instant type generation
  • Nested object support
  • Array inference
  • Private browser processing
  • Copy or download output
  • Mobile friendly

Frequently Asked Questions

Is it free?

Yes. Generate types as often as you need with no fee or sign-up.

Is my JSON uploaded?

No. Everything runs locally in your browser.

Does it support nested objects?

Yes. Nested objects become separate interfaces with stable naming.

Can arrays generate types?

Yes. Element types are inferred, including unions for mixed arrays.

Can I rename the root interface?

Yes. Use the Root Interface Name field (desktop toolbar or mobile TYPESCRIPT sheet) before you generate.

Does it work with API responses?

Yes. Paste a real response JSON to model your client types, then adjust in code as contracts evolve.

What if my JSON is invalid?

Use the JSON Formatter or JSON Validator to fix syntax, then try again.

Can I use it on mobile?

Yes. Use Generate on the sticky bar and export from the TYPESCRIPT sheet.

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