How the json formatter works
The formatter parses your input with the browser's built-in JSON parser (which validates it against the JSON specification), then re-serializes it with consistent indentation. If parsing fails, the tool shows the error instead of a formatted result — a quick way to spot a missing comma or bracket.
Step-by-step guide
- Paste your raw or minified JSON into the box.
- Choose your preferred indentation.
- Read the beautified, validated output — or the parse error if the JSON is invalid.
Common uses
- Debugging an API response that came back as a single unreadable line
- Validating a config file before committing it
- Cleaning up JSON before sharing it in documentation
Frequently asked questions
The tool shows a validation error describing what the browser's parser found wrong (such as a trailing comma or unmatched bracket), instead of formatted output.
No — formatting and validation both happen locally in your browser using JavaScript's built-in JSON.parse and JSON.stringify.
It can handle typical API payloads and config files well; extremely large files (multiple megabytes) may slow down as-you-type formatting in older browsers.