JSON to TypeScript types
Paste any JSON and instantly generate a TypeScript type definition.
Objects and arrays are inspected to infer field names and nested shapes,
so you can drop the output straight into your codebase.
Nothing is sent to a server—parsing and type generation run entirely in your browser.
JSON to TypeScript Type & Interface Generator
Automatically generate TypeScript interface and type definitions with just one click by parsing sample JSON responses or dummy data payloads.
This drastically cuts down the hours spent manually writing type definition files required for strict type enforcement in modern frontend development frameworks (like Next.js, React, or Vue). It seamlessly parses deeply nested objects and arrays, integrating smoothly into your secure, local workflow.
Common use cases
- Type API responses: Paste a real response body and create a starting point for frontend types.
- Document payload shape: Turn sample JSON into readable TypeScript definitions for teammates.
- Speed up prototyping: Generate temporary interfaces while exploring unfamiliar APIs.
Review before production
Generated types are inferred from the sample you provide. If an API can return optional fields, nullable values, mixed arrays, or error responses, review the generated result and adjust it to match the real contract.
Articles for this tool
How to Automatically Generate TypeScript Definitions from JSON
Learn how to efficiently create type-safe TypeScript interfaces and type definitions from JSON data like API responses.
Mastering the JSON Ecosystem: Best Practices for Type Safety and Schema Management
JSON is more than just a data format; it's the backbone of modern development. From TypeScript types and Zod validation to OpenAPI documentation, learn how to leverage the modern JSON ecosystem.
JSON Formatting and Validation: How to Read API Responses Safely
Learn how to format JSON, catch syntax errors, inspect value types, and turn API responses into types, schemas, or documentation.
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