JSON to TypeScript Converter
Generate readable TypeScript types from real JSON, including nested objects and arrays.
Your privacy is safe, this tool runs entirely in your browser. Nothing you enter is uploaded to or stored on our servers.
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How to use JSON to TypeScript Converter
- 1Paste a JSON object or array.
- 2Name the root type and choose interface or type output.
- 3Adjust optional and readonly property settings.
- 4Copy or download the generated TypeScript.
Generate useful types from API examples
This JSON to TypeScript converter inspects values, creates nested declarations and combines array element types. It also quotes property names that are not valid JavaScript identifiers.
Generated types describe the sample you provide. Review nullable fields and optional API properties against the real API contract before using them in production.
Frequently asked questions
Can it generate nested interfaces?
Yes. Nested objects become separately named interfaces, including objects found inside arrays.
How are mixed arrays handled?
The generator combines distinct element types into a TypeScript union.
What happens to null values?
A null-only value becomes unknown | null because JSON does not reveal the intended non-null type.
Is the JSON uploaded?
No. Parsing and TypeScript generation run locally in your browser.