Free JSON Formatter & Validator

Paste JSON to pretty-print, minify, or validate it · with the exact line and position of any syntax error.

Frequently asked

Is it safe to paste API responses with real data?

Yes · parsing and formatting run entirely in your browser. Nothing is transmitted or stored. Even so, avoid pasting secrets anywhere out of habit · and scan your app if you're not sure what your API exposes.

Why does my JSON fail with a trailing comma?

Strict JSON forbids trailing commas, single quotes, comments, and unquoted keys · all legal in JavaScript objects but not in JSON. The validator pinpoints the offending character so you can fix it fast.

Related tools

  • JSON to TypeScript · Convert a JSON payload into TypeScript interfaces · nested objects and arrays included · ready to paste into your codebase.
  • CSV ↔ JSON Converter · Convert between CSV and JSON in either direction · with proper handling of quoted fields, commas inside values, and headers.
  • Base64 Encoder / Decoder · Encode text to Base64 or decode it back · with full UTF-8 support. Handy for inspecting tokens, data URIs, and encoded config.

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