Key Features
Beautify minified JSON with proper indentation
Minify JSON to reduce file size
Validate JSON and pinpoint syntax errors with line numbers
Syntax highlighting for keys, strings, numbers, and booleans
Collapsible tree view for nested objects and arrays
One-click copy of formatted or minified output
How to Use
1Paste your JSON into the input area
2Click Format to beautify, or Minify to compress
3Review any validation errors with line-number references
4Click Copy to grab the result
Common Use Cases
Debug API responses that return minified JSON
Validate a JSON config file before deployment
Read and understand large nested JSON structures
Prepare JSON payloads for HTTP requests
Frequently Asked Questions
Does this work with JSON5 or JSONC?
The formatter supports standard JSON (RFC 8259). JSON5 features like trailing commas or unquoted keys will be flagged as errors.
Is there a file size limit?
The formatter handles JSON up to several megabytes in modern browsers. Very large files may slow down the tree view — use Minify mode for best performance.
Is my JSON data sent to a server?
No. All parsing and formatting happens in your browser. Your data never leaves your device.
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