JSON to TypeScript Interface Generator
Generate TypeScript interfaces or types from a JSON sample
How it works
- 1Paste JSON
Drop a sample response, config, or object literal.
- 2Name the root type
Set the top-level type name (defaults to 'Root').
- 3Copy the TypeScript
Get an interface (or type alias) definition for every nested object.
About JSON to TypeScript Interface Generator
Free online JSON to TypeScript converter. Paste a JSON sample to generate clean TypeScript interfaces or type aliases, with automatic nested-type extraction and array union inference. Runs entirely in your browser. JSON to TypeScript Interface Generator on 712 Tools runs entirely inside your browser using modern JavaScript APIs — no server ever sees your data. That means instant results, complete privacy, and no upload limits.
Whether you need to generate typescript interfaces or types from a json sample for a debugging session, a quick sanity check, or a production incident, this tool is free to use as many times as you need. There are no watermarks, no sign-up, and no ads inside the tool itself.
Frequently asked questions
How are arrays typed?
Element types are inferred and merged: a mixed [1, 'a'] becomes Array<number | string>.
Interface vs type?
Interfaces are extensible via declaration merging; types are more flexible with unions and mapped types. Toggle in the UI to switch.
What about optional fields?
Only the fields present in your sample are emitted. Merge multiple samples with a union type if some fields are conditionally present.
Read more
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