JSON Formatter & Validator

Paste messy or minified JSON and get clean, indented, validated output instantly. Everything runs in your browser, so the data you paste never touches a server.

100% freeNo sign-upRuns in your browserNo upload · data stays private

📖 Read the full JSON Formatter & Validator guide — how it works, examples & FAQ →

How to use this tool

  1. Paste your JSON into the input box.
  2. Choose Beautify (indented) or Minify (single line).
  3. Copy the validated output — if it's invalid, you'll see exactly what broke.

Example

{"a":1,"b":[2,3]} → pretty-printed with 2-space indent

Why it's private

This tool runs entirely in your browser using JavaScript. Whatever you paste is processed on your own device — it is never uploaded to a server, logged, or stored. Built by Calabi, which also strips AI metadata and C2PA signals from images and video.

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