Free JSON to TypeScript Converter

Generate TypeScript interfaces from any JSON data. Handles nested objects, arrays, union types, and optional properties. Instant, free, private.

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TypeScript Interfaces

Why Generate TypeScript from JSON?

Converting JSON to TypeScript interfaces provides several key benefits:

Type Safety: Catch errors at compile time instead of runtime.
API Contracts: Document API responses and ensure consistency.
Faster Development: Reduce boilerplate and get instant type definitions.
Better IDE Support: Autocomplete and inline documentation.
Refactoring Confidence: Change code knowing types will catch breaking changes.

Nested Objects: Automatically generates interfaces for nested structures.
Arrays: Infers array element types and handles unions.
Union Types: Detects when properties can be multiple types.
Optional Properties: Marks properties as optional when not all objects have them.
Primitive Types: Correctly identifies strings, numbers, booleans, and nulls.
Complex Nesting: Handles deeply nested data structures.

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Instant Generation

Generate interfaces in milliseconds. No server calls, no waiting.

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100% Private

All processing happens in your browser. Your data never leaves your computer.

0️⃣

Zero Dependencies

Pure JavaScript. No frameworks, no libraries, no bloat.

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Smart Type Inference

Intelligently detects types, unions, and optional fields.

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Syntax Highlighted

Beautiful, readable output with syntax highlighting.

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Easy Copy

One-click copy to clipboard. Ready to paste into your project.

Feature	json.express	quicktype.io	json2ts.com
Private (no upload)	✓
TypeScript generation	✓	✓	✓
Union types	✓	✓
Zero dependencies	✓
Free	✓	✓	✓
No ads	✓

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