JSON to TypeScript converter.
Convert JSON to TypeScript interfaces or Zod schemas. Toggle strict vs loose nulls, copy Zod output, and generate types from API responses — free, in-browser.
Options
Null handling
Output format
TypeScript output
Paste JSON to generate types
Choose TypeScript, Zod, or Yup output. Toggle strict null handling for optional fields, then press ⌘↵ to regenerate.
How to use the JSON to TypeScript converter
- Paste a representative payload into the input panel so this JSON to TypeScript converter can infer stable field types from realistic data.
- Pick your output target such as interfaces, Zod, or Yup depending on whether you need compile-time typing, runtime validation, or both.
- Adjust strict-null, readonly, and export options to match your codebase conventions and generate TypeScript interfaces from JSON safely.
- Copy the result into your project and pair it with tests to catch response-shape regressions whenever upstream APIs change.
What is JSON to TypeScript Conversion?
A JSON to TypeScript converter transforms raw JSON payloads into strongly typed models that improve autocomplete, compile-time safety, and API reliability. Instead of hand-writing interfaces for every endpoint, you can generate TypeScript interfaces from JSON samples and iterate faster as contracts evolve. This tool analyzes primitives, nested objects, arrays, and nullable fields, then outputs idiomatic type definitions or validation-ready schemas such as Zod and Yup. Teams also use it as a JSON interface generator during backend integration, because it reduces mismatch bugs caused by undocumented response changes. If you need runtime guarantees, generated validators can complement static typing by enforcing shape checks at boundaries. Because all conversion happens client-side, private payloads stay local while you experiment with options like strict null handling, readonly fields, and export style. The result is a faster path from uncertain API data to trustworthy application types.
Frequently asked questions
What output formats are supported?+
The converter supports TypeScript interfaces or type aliases, plus Zod and Yup schema generation for runtime validation. This flexibility lets you pick a workflow that fits your stack, from static types only to combined type-safety and validation pipelines.
How does it handle nested objects and arrays?+
Nested objects are converted into reusable referenced structures, and arrays are inferred based on detected element shapes. Complex payloads are traversed recursively, so deeply nested API responses still produce consistent and readable generated TypeScript output.
What are the configuration options?+
You can control export style, readonly modifiers, strict null behavior, and whether output uses interfaces or type aliases. These options help you align generated code with existing lint rules, architecture standards, and preferred domain modeling patterns.
Can I use this for API response typing?+
Yes. This is a common json to typescript interface generator free workflow for frontend and backend teams. Paste a representative API response, generate types, then place them near your client layer so contract drift is caught early.