JSON Formatter
Validate, beautify and minify JSON with clear error hints
How to Use
JSON is the most common data format in everyday development — API responses, config files and logs are full of it. Pasting a minified blob of JSON is painful to read; this tool beautifies, validates and highlights it in one click, and points out exactly where syntax errors are.
How to use: paste your JSON into the input box and click "Format" to pretty-print, or "Minify" to strip whitespace. If the JSON is invalid, the tool reports the reason and approximate line number. Everything runs locally in your browser — your data never leaves your device.
FAQ
Does this tool upload my JSON data?
No. All formatting and validation happens locally in your browser. Your data never touches our servers, so it's safe for sensitive JSON.
How do I find the problem when validation fails?
The tool shows the error reason and approximate line number. The most common causes are trailing commas, unmatched quotes, single quotes instead of double quotes, or unescaped special characters.
How large a JSON file can it handle?
Since processing is local, JSON up to a few megabytes usually works smoothly. For very large files, a local editor or CLI tool is recommended.