JSON to TypeScript
Turn a sample JSON value into TypeScript interfaces — nested objects become their own interfaces and array items are merged.
Your JSON
Paste a JSON value and get TypeScript types. Types are inferred from this one sample — review before shipping.
No types yet
Paste a JSON value above, then press “Generate types”.
Inferred from a single sample: keys missing from some array items become optional, and everything else is required. Nested and array items get their own interfaces.
Runs entirely in your browser. Nothing is uploaded.
How it works
This utility runs locally in your browser for privacy and speed.
1 ⚡
Unlimited local toolsThis run costs 1 credit(s) and is saved to your history automatically.
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Frequently asked questions
- Do I get free credits to try JSON to TypeScript?
- Yes — new accounts get 3 free credits to spend on any tool, JSON to TypeScript included. After that you only pay for what you run.
- How many credits does JSON to TypeScript cost?
- Everything runs in your browser and nothing is uploaded: free accounts pay 1 credit per run, and Pro or Pro+ members run it as often as they like.
- Is the content I paste private?
- JSON to TypeScript uses your input only to generate the result. Stored results are deleted automatically by our retention policy, and you can remove any run from your history.
- Do I need to install anything?
- No. JSON to TypeScript works in any modern browser — nothing to download or install.
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