JSON Formatter & Validator
Beautify, minify and validate JSON with error locations.
Loading tool…
Processing happens on your device using your browser's CPU/GPU. Results are kept only in this tab's memory and are wiped when you click “Clear” or close the page.
About JSON Formatter & Validator
JSON that arrives from an API or a log file is usually one long unreadable line, and a single missing comma breaks it. Paste it here and the tool re-indents it, tells you whether it is valid, and points at the exact line and column where parsing failed. Developers, students learning APIs and anyone editing a config file can use it. The text is parsed by JavaScript in your own browser and never uploaded.
How to use JSON Formatter & Validator
- Paste your JSON into the left pane, or use Open file to load a .json file.
- Pick an indent of 2 spaces, 4 spaces or tabs, and tick Sort keys A-Z if you want a stable order.
- Click Format to beautify, or Minify to strip every space for production.
- Read the green valid badge or the red error with its line and column number.
- Copy the result or download it as formatted.json.
What people use it for
- Making an API response readable before you debug why a field is missing
- Checking a package.json, tsconfig or Firebase config for a stray comma
- Minifying JSON before pasting it into a request body or an environment variable
- Sorting keys so two versions of the same config can be compared line by line
Good to know
It accepts standard JSON only, so comments, trailing commas and single quotes are reported as errors rather than silently fixed. Very large files depend on your device's memory, since the whole document is parsed at once. Formatting never changes your data, only the whitespace and, if you ask, the key order.