JSON to TypeScript

Generate TypeScript interfaces from any JSON automatically.

JSON ToolsBrowser-only • PrivateFree

JSON Input

TypeScript Interfaces

Output will appear here...

Privacy First: All processing happens locally in your browser. Your data never leaves your device and is never uploaded to any server.

About JSON to TypeScript

The JSON to TypeScript generator infers strongly-typed interfaces from a sample JSON payload, so you can stop hand-writing types for API responses. Nested objects become their own named interfaces, arrays are typed by their element, and null or missing fields are marked optional. Everything is generated in your browser, so you can safely paste real production responses. Combine it with the JSON Formatter to tidy the sample first, or the JSON Schema Generator for validation schemas.

How to Use

1Open JSON to TypeScript and paste or type your data into the input area.
2Adjust any available options to match the result you want.
3Your output is generated instantly — no button-clicking required for most tools.
4Use the Copy or Download button to save your result.

Common Use Cases

Debugging API responses while building web and mobile apps
Cleaning up minified or messy JSON from logs and network tabs
Preparing configuration files and fixtures for testing
Converting data between JSON and other formats for imports/exports

Frequently Asked Questions

How are nested objects typed?

Each nested object is extracted into its own named interface and referenced from the parent, so you get clean, reusable types instead of one giant inline structure.

How does it decide which fields are optional?

Fields that are null, or that don't appear in every object of an array, are marked optional with a question mark so the generated interface reflects the real shape of your data.

Is JSON to TypeScript free to use?

Yes. JSON to TypeScript is completely free with no sign-up, no subscription, and no usage limits. Every tool on CodeUtilityKit is free forever.

Is my data safe when I use JSON to TypeScript?

Absolutely. JSON to TypeScript runs entirely in your browser. Your input is processed locally with JavaScript and is never sent to, stored on, or logged by any server — so it is safe even for private or sensitive data.