JSON to TypeScript & Go

Free · no sign-up

Paste JSON and get typed TypeScript interfaces or Go structs — inferred in your browser.

Root type name

interface Root {
  id: number;
  name: string;
  active: boolean;
  roles: string[];
  address: Address;
  scores: number[];
}

interface Address {
  city: string;
  zip: string;
}

Paste a JSON sample and get ready-to-use TypeScript interfaces or Go structs. The types are inferred in your browser — nested objects become their own named types, and arrays of objects are merged into one shape with optional fields where keys are missing. Nothing is uploaded.

✓TypeScript interfaces or Go structs
✓Named types for nested objects
✓Merges arrays of objects, marks optional fields
✓Go output includes json struct tags
✓Runs in your browser — nothing uploaded

Who it's for

Typing an API response
Scaffolding a Go struct from a payload
Turning a config sample into types
Sharing a data shape with your team

How it works

1Paste a JSON object or array.
2Pick TypeScript or Go.
3Name the root type if you like.
4Copy the generated types.

Frequently asked questions

How does it handle arrays of objects?+

It merges every element into one type. A key that appears in some elements but not all becomes optional (a `?` field in TypeScript, `omitempty` in Go).

Does it know int vs float in Go?+

Yes — a whole number becomes `int` and a decimal becomes `float64`. If an array mixes both, it uses `float64`.

What about null values?+

A null becomes `null` in TypeScript and `interface{}` in Go, since the real type can't be inferred from null alone.

Is my JSON uploaded?+

No. The types are generated entirely in your browser; your data never leaves your device.