Convert JSON to TypeScript Types Online
Writing TypeScript interfaces by hand from an API response or JSON schema is tedious and error-prone, especially for large nested payloads. This tool generates accurate TypeScript type definitions from any JSON, inferring interfaces, union types, arrays, and optional fields automatically. Paste your JSON and get clean, copy-ready TypeScript types in seconds. All processing runs in your browser, so confidential API payloads never leave your device. This is ideal for bootstrapping types when integrating with third-party APIs or when migrating a JavaScript project to TypeScript.
json input
0 chars1 lines
typescript interfacesREADY
0 chars1 lines
FAQ
- What TypeScript constructs does this generate?
- The tool generates interface declarations for objects, typed arrays, union types for fields with mixed values, and marks fields optional when they are absent in some objects.
- Can I use it for nested JSON?
- Yes. Deeply nested objects each get their own named interface, and array element types are inferred from the array contents.
- Does it handle null values?
- Yes. Fields that are null in the input are typed as the inferred type unioned with null, for example string | null.