JSON Formatter
Free online JSON formatter and validator. Prettify or minify JSON instantly in your browser. No data sent to servers. Works offline.
How to Use
- Paste your JSON into the input box.
- Click Format to prettify with 2-space indentation.
- Click Minify to compress into a single line.
- Click Validate to check for syntax errors without modifying output.
- Click Copy to copy the result to clipboard.
About JSON Formatter
JSON (JavaScript Object Notation) is the most common data interchange format. A formatter makes nested structures readable by adding indentation, while a minifier strips whitespace to reduce payload size. Both operations are lossless — the parsed value is identical.
This tool runs entirely in your browser. No data ever leaves your machine.
FAQ
Is my JSON data sent to any server?
No. All processing happens entirely in your browser using JavaScript. Nothing is sent to any server.
What does the Validate button do?
It checks whether your JSON is syntactically valid and shows the error location if not.
What indentation does the formatter use?
2 spaces by default, which is the most common convention for JSON.
Can I use this on mobile?
Yes, ZeroTool is fully responsive and works on any device.