One document, or several samples as JSON Lines.
Options for TypeScript
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Turn JSON into TypeScript, Go, Zod, Rust and more

Free, no sign-up, no credit card, no trial. Your JSON never leaves the browser — paste a sample and get typed code instantly: TypeScript interfaces, a Zod schema, Go structs, a JSON Schema, Python, Rust, Kotlin, Swift or C#.

Nine languages

TypeScript, Zod, Go, JSON Schema, Python, Rust, Kotlin, Swift and C# — from one JSON sample.

Every sample, every item

Optional fields, unions, nullable values and big numbers are found across the whole sample, and the output is compiled in the tests.

A page per language, with options

Each language has its own page and options (interface or type, omitempty, strict schemas…), remembered for next time.

Private & client-side

Your JSON never leaves the browser. No server round trip, ever.

Choose a language

JSON to TypeScript interfacesJSON to a Zod schemaJSON to Go structsGenerate a JSON Schema from JSONJSON to Python classesJSON to Rust structsJSON to Kotlin data classesJSON to Swift Codable structsJSON to C# classes

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Frequently asked questions

What can I generate from JSON?
TypeScript interfaces, Zod schemas, Go structs with json tags, a JSON Schema (draft 2020-12), Python Pydantic models or dataclasses, Rust serde structs, Kotlin data classes, Swift Codable structs and C# records or classes. Paste a JSON sample, pick a language, and the typed code appears instantly — each language has its own page and its own options, remembered for next time.
How accurate are the generated types?
Every item of every array and every sample is read, not just the first: a field missing from some records is optional, a field with two kinds of value becomes a union (or the language's any-value type), null beside a value makes it nullable, and integers past 2^53 or int64 are noticed. Names are always valid in the target language (keys starting with a digit, reserved words, clashing keys like first_name and first-name), and the output is proved by tests that compile the TypeScript, build and run the Go, validate the sample with the Zod schema and the JSON Schema, and compile the Rust. Paste several samples as JSON Lines to merge them.
Is my JSON uploaded anywhere?
No. Parsing and generation run entirely in your browser, so your JSON — including API responses — never leaves your device. It's free with no sign-up.

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