About JSON Formatter
Format, beautify, and validate JSON instantly. Paste minified or messy JSON to get clean, indented output — and catch syntax errors with a clear message. Everything runs in your browser.
How to Use
- Paste your JSON into the input box.
- The tool validates it and reports any syntax error with its location.
- Read the beautified, indented output.
- Copy the formatted JSON for use in your code.
Why Use This Tool?
- Accurate — built on precise, well-tested mathematical formulas.
- Instant — all calculations happen client-side for zero latency.
- Private — no data is sent to any server; your information stays on your device.
- Free — no sign-up, no limits, no hidden costs.
Frequently Asked Questions
Why is my JSON invalid?
The most common causes are trailing commas, single quotes instead of double quotes, missing quotes around keys, or unclosed brackets. The formatter points to where parsing failed.
Is my data sent to a server?
No. Formatting and validation happen entirely in your browser, so you can safely paste sensitive JSON — nothing is uploaded.
What is the difference between formatting and minifying?
Formatting (beautifying) adds indentation and line breaks for readability; minifying removes all whitespace to make the payload as small as possible for transmission.