Does it handle nested objects and arrays?

Yes. Nested objects become separate named interfaces, arrays become typed arrays (e.g. string[]), and arrays with mixed types become unions like (string | number)[].

Is my JSON sent anywhere?

No — the conversion runs entirely in your browser. Nothing is uploaded.

What if a field can be null?

A null value is typed as null; if you have multiple samples, combine them so optional or nullable fields show up. For full nullability you may want to hand-tweak the output.

JSON to Code & TypeScript Model Generator

Generate TypeScript, Go, Python, Java, C#, Rust, Swift and Kotlin models from JSON with nested types and optional fields.

Source & Options

Target languageRoot type name

Types only (where supported)JSON sample

Import File

Generated Code

Inferred models describe your sample, not every possible API response. Review nullable and optional fields, number precision and generated library imports before production use. Code generation uses quicktype locally; no sample is uploaded.

Loading Tool…

What Is the JSON to Code & TypeScript Model Generator?

Generate typed models from JSON in TypeScript, Go, Python, Java, C#, Rust, Swift or Kotlin using the local quicktype engine. Nested objects become named types, arrays infer their item types, and varied object samples expose optional or nullable fields. Choose a root name and generate types alone where supported, or include the target's serialization helpers. The output is a starting point: review application constraints, number precision, dependencies and possible values not present in the sample before using it in production. Input is not uploaded.

How It Works

Paste or import a JSON sample, select TypeScript, Go, Python, Java, C#, Rust, Swift or Kotlin, and choose a root type name. Generate the code, then review and download it. Use an array of varied examples to expose optional fields. Types-only output is available where the target language supports it.

When to Use It

Use it when integrating a third-party API, converting untyped JavaScript to TypeScript, generating model types from sample data, or documenting the shape of a JSON payload.

Frequently Asked Questions

Does it handle nested objects and arrays?: Yes. Nested objects become separate named interfaces, arrays become typed arrays (e.g. string[]), and arrays with mixed types become unions like (string | number)[].
Is my JSON sent anywhere?: No — the conversion runs entirely in your browser. Nothing is uploaded.
What if a field can be null?: A null value is typed as null; if you have multiple samples, combine them so optional or nullable fields show up. For full nullability you may want to hand-tweak the output.

Found an issue? Send Feedback. See our data sources and update policy for tools that depend on changing information.