What this tool helps with
A free online tool to format, validate, repair, beautify, and minify your JSON data. Instantly pretty-print JSON, auto-fix common syntax issues with a JSON repair engine, check for errors with a powerful linter, and compress it for production use.
Recommended workflow
- 1Select Mode - Click "Format", "Compress", "Validate", or "Repair" button
- 2Input JSON - Paste or enter raw/possibly broken JSON string in the input box
- 3Execute Processing - Click the corresponding processing button to run the selected mode
- 4View Results - Review the formatted, compressed, validated, or repaired JSON; copy results or download as a JSON file
Capability details
- JSON Formatting - Beautify JSON with indentation and line breaks for readability
- JSON Compression - Remove whitespace to minimize file size for production
- JSON Validation - Check syntax errors with detailed error messages and linting
- JSON Repair - Automatically fix common JSON issues like missing quotes, trailing commas, and comments via a repair engine
- File Statistics - Display original size, processed size, and compression ratio (where applicable)
- One-click Copy - Quickly copy processing results to the clipboard
- File Download - Save processed JSON as a file
Practical use cases
- API Development - Format, validate, and repair API response data for easier debugging
- Configuration Files - Beautify and fix JSON config files for better readability and maintenance
- Data Transmission - Compress JSON data to reduce network transfer size
- Error Recovery - Repair accidentally broken JSON pasted from logs, editors, or copy-paste operations
- Code Review - Validate and repair JSON format to ensure data correctness before merging
- Database Import - Validate and repair JSON data format before importing it into a database
Privacy, rights, and limits
Most processing is designed to run in the browser whenever possible, which makes the tool useful for quick personal or work files. For sensitive, production, or regulated material, test with a sample first and confirm the target platform's format, size, and quality requirements.
Common questions
Does JSON formatting change my data?
No. Formatting only changes whitespace, indentation, and line breaks. It does not change valid field names, values, or object structure.
What JSON errors can the repair mode fix?
It can often fix missing quotes, trailing commas, comments, single quotes, and common copy-paste issues. Severely broken structure may still need manual review.
Is my JSON uploaded to a server?
The tool processes content in the browser, making it useful for API debugging, config review, and temporary formatting of sensitive payloads.