JSON to TypeScript
JSON to TypeScript — Generate TypeScript Interfaces from JSON Online
What is JSON to TypeScript?
Generate TypeScript interfaces from JSON. Paste JSON and get type definitions for your frontend or API.
Convert JSON to TypeScript interfaces in one click. Paste a sample JSON object and get a TypeScript interface or type definition. Use it for API contracts, frontend models, or documentation. The tool infers types from your data and outputs ready-to-use code. All processing runs in your browser—no data is sent to any server. Part of the formatterjson.org developer data tools platform.
How to Use JSON to TypeScript
- Paste or type your input into the editor on the left panel.
- Results update automatically while you type. You can also press Ctrl+Enter to force a refresh.
- View the result in the output panel on the right with full syntax highlighting.
- Use Copy or Download to export the result.
- Drag and drop
.jsonor.txtfiles directly into the editor. - Toggle Tree View for an interactive, collapsible view of the JSON structure.
Example
Input:
{"name":"John","age":30,"active":true}Output:
interface Root {
name: string;
age: number;
active: boolean;
}
Common Use Cases
- API response types
- Frontend models
- Documentation
- Type-safe clients
Common Errors
- Invalid JSON
- Trailing commas
- Single quotes
- Unquoted keys
Why Use Our JSON to TypeScript?
- 100% client-side — your data never leaves your browser. No server processing, no data collection.
- No sign-up required — start using the tool instantly with no registration or installation.
- Keyboard shortcuts — press Ctrl+Enter to run, ? for shortcuts list, Ctrl+B to toggle sidebar.
- Persistent state — your input is automatically saved across sessions using local storage.
- IDE-style interface — Monaco Editor (the engine behind VS Code) with syntax highlighting and error detection.
- Multi-format conversion — convert between JSON, XML, CSV, and YAML without switching tools.
Frequently Asked Questions
What does JSON to TypeScript do?
It takes a JSON object and generates TypeScript interface or type definitions so you can use type-safe code with that structure.
Is the output ready to use?
Yes. Copy the generated interface into your project. You may want to rename "Root" to match your domain.
Does it handle nested objects?
Yes. Nested objects are inlined as object types. For very deep structures you might refactor into separate interfaces.
Is my JSON sent to a server?
No. Conversion runs entirely in your browser. Your data never leaves your device.
Can I use this for APIs?
Yes. Paste a sample API response to generate types for your client or tests.
Try JSON to TypeScript Now
Paste your data into the editor above for instant processing. Use Ctrl+Enter anytime to re-run quickly.