Transform Data

JSON to TypeScript

Generate a TypeScript interface from a sample JSON object. The result is generated locally in your browser.

Transform Data - local browser run

What this tool is for

JSON to TypeScript creates a starter interface from a representative JSON sample.

When to use it

Use it when you need quick client-side types for an API response, fixture, or local data file.

What the result means

The result is an interface named GeneratedType with inferred primitive, array, object, nullable, and mixed union types.

Use notes

  • Use a sample that includes the fields you expect in real data.
  • Review optional fields manually; one sample cannot prove a key is always present.
  • Rename the generated interface before committing it.

Privacy and limits

Everything runs in your browser tab. Avoid pasting production secrets, private tokens, customer data, or proprietary code into any online page unless your team policy allows it.