JSON Formatter & Validator
Format messy JSON beautifully, minify it, or validate it with one paste. Broken syntax gets flagged instantly so you can fix it - free, instant, and private, since everything runs in your browser.
Privacy note: Your JSON is parsed only in your browser — it is never uploaded or stored anywhere.
How to use
- Paste your JSON into the input box (or click Load Sample JSON to try it out).
- Click Format to pretty-print it, Minify to compress it, or Validate to only check it.
- If the JSON is valid you will see a green confirmation with key count and size stats; if not, the exact parser error is shown in red.
- Copy the output or download it as a .json file.
Tips
- Paste API responses here first when debugging - formatting reveals structure that one-line JSON hides.
- Watch for the two classic errors: trailing commas and unquoted keys.
- Minify before pasting JSON into URLs or size-limited fields.
- Your data never leaves the browser, so pasting API keys in test payloads stays local.