JSON to TypeScript Converter
Paste JSON and get TypeScript interfaces instantly. No more writing types by hand—the tool figures out the structure and generates proper TypeScript code. Handles nested objects, arrays, unions, and optional fields. Copy the code and use it in your project right away.
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Input (JSON)
Output (TypeScript)
Frequently Asked Questions
Why would I need this?
Writing TypeScript interfaces manually is tedious, especially for big API responses. This tool looks at your JSON and writes the types for you. Saves time and catches edge cases you might miss. Super useful when working with APIs that don't provide TypeScript definitions.
How accurate are the generated types?
Pretty good, but not perfect. The tool infers types from the JSON you give it, so if your sample data doesn't show all possibilities, the types might be incomplete. For example, if a field is sometimes a string and sometimes null, but your sample only has a string, it'll miss the null case. Always double-check the output.
Does it handle nested objects and arrays?
Yep. Nested objects become their own interfaces, and arrays are typed properly (like `string[]` or `User[]`). If you have complex nested structures, it creates multiple interfaces that reference each other.
Is this secure?
Everything runs in your browser. Your JSON doesn't go anywhere—it's processed locally and never uploaded to a server.