JSON → TypeScript Interface
Nested objects, unions, null handling
Quick guide
What can JSON to TypeScript Interface help you do?
Free online JSON to TypeScript interface converter. Handles nested objects, arrays, null, and union types. Copy and paste into your project.
Best for
JSON to TypeScript Interface helps with quick debugging, API data cleanup, format checks, and small code or config tasks without opening an IDE or installing a package.
How to use it
For JSON to TypeScript Interface, paste the text, code, or configuration into the input area, choose the mode you need, and run it. For large data, test a small sample first.
How to read the result
After using JSON to TypeScript Interface, the output is kept copy-friendly for docs, code, and config files. When validation is available, fix the reported error location before trusting the final output.
Privacy and limits
When using JSON to TypeScript Interface, most processing happens in the browser. Do not paste passwords, private keys, tokens, or unmasked production data into any online tool.
For JSON to TypeScript Interface: Developer tools are for quick inspection and conversion. They do not replace tests, linting, security review, or version control.
Frequently Asked Questions
How is null handled?
A null value is inferred as the literal null type.
Arrays with multiple types?
Auto-merged into union: (string | number)[].
Deep nesting?
Nested objects produce referenced sub-interfaces. Practical depth is limited by browser memory and the JavaScript call stack.