JSON formatter & validator
Paste JSON to format it with proper indentation, minify it to a single line, or catch syntax errors instantly. Everything runs in your browser.
How it works
What does the formatter do?
"Format" pretty-prints your JSON with 2-space indentation, making nested structures easy to read. "Minify" removes all whitespace to produce the most compact valid representation — useful before sending JSON in a request body or storing it.
How does real-time validation work?
The tool uses the browser's native JSON.parse to validate as you type. If your JSON is invalid, the error message from the parser is shown inline, including the line number where the syntax error was detected.
Is my data sent anywhere?
No. Parsing and formatting all happen in your browser using native JavaScript APIs. Nothing you paste is transmitted over the network.
What can I do with the output?
Copy it to clipboard with one click, or download it as a .json file. On iOS, the download triggers the share sheet so you can save it to Files.