Online JSON Formatter, Validator, Repair & Beautifier - Master Tools

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.

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Online JSON Formatter, Validator, Repair & Beautifier

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.

Features

JSON Formatting
JSON Compression
JSON Validation
JSON Repair
+1 more features

Usage Examples

Basic Usage

JSON Tools Usage Example

Usage Steps:

  1. Select Mode - Click "Format", "Compress", "Validate", or "Repair" button
  2. Input JSON - Paste or enter raw/possibly broken JSON string in the input box
  3. Execute Processing - Click the corresponding processing button to run the selected mode
  4. View Results - Review the formatted, compressed, validated, or repaired JSON; copy results or download as a JSON file

Features:

  • 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

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

Common Questions (Q&A):

  1. Q: Does JSON formatting change my data?
    A: No. Formatting only changes whitespace, indentation, and line breaks. It does not change valid field names, values, or object structure.
  2. Q: What JSON errors can the repair mode fix?
    A: It can often fix missing quotes, trailing commas, comments, single quotes, and common copy-paste issues. Severely broken structure may still need manual review.
  3. Q: Is my JSON uploaded to a server?
    A: The tool processes content in the browser, making it useful for API debugging, config review, and temporary formatting of sensitive payloads.
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