JSON to TypeScript
Generate a TypeScript interface from JSON, inferring property types automatically.
Paste JSON below - this tool infers property types and generates a matching TypeScript interface, with nested interfaces for nested objects.
Type inference from a single JSON sample is a best guess - review the generated types, especially for fields that could reasonably be optional or a union of types.
What Does This Tool Do?
It analyzes your JSON's structure and generates a TypeScript interface declaration with property types inferred from the actual values - strings, numbers, booleans, arrays, and nested objects (as their own nested interfaces).
Why Use This Tool?
Writing TypeScript interfaces by hand for a large API response is tedious and error-prone - this tool generates a solid starting point instantly from a real example response.
How to Use It
- Paste a sample JSON object (ideally a realistic, representative example).
- Click Convert.
- Copy the generated interface(s) into your TypeScript project.
Limitations
Type inference from one JSON sample is necessarily a best guess - a field that's sometimes null, sometimes a number, won't be perfectly captured from a single example. Review and adjust the generated types (especially optional fields marked with ?) for your actual data's full range.