JSON Formatter & Validator
Format, minify, and validate your JSON data instantly
JSON Input
About JSON Formatter
Paste your JSON data above and click “Format” to pretty-print it with proper indentation. Use “Minify” to compress it into a single line. The validator will automatically check for syntax errors.
Frequently Asked Questions
How do I format minified JSON into readable output?
Paste the minified JSON into the input field and click Format. The tool re-indents every key-value pair and array element with your chosen indentation (2 spaces, 4 spaces, or tab), producing human-readable output instantly. The status bar also confirms whether the JSON is syntactically valid, so you catch errors at the same time.
Is my JSON data sent to a server when I use this formatter?
No. The JSON Formatter runs entirely in your browser using JavaScript. Your data is never uploaded to any server, making it safe to paste credentials, API responses, or other sensitive payloads. The formatting and validation logic executes locally, so it even works offline after the page loads.
Can this tool tell me exactly where a JSON syntax error is?
The validator uses the browser’s native JSON.parse under the hood, which surfaces a human-readable error message including the approximate character position of the first syntax error. Common mistakes like trailing commas, missing quotes, or mismatched brackets are flagged immediately in the status bar below the input.
What is the difference between Format and Minify in a JSON tool?
Format adds whitespace and newlines to make JSON easy to read; Minify removes all unnecessary whitespace to produce the most compact representation. Minified JSON is what you typically send over the wire in API requests to reduce payload size, while formatted JSON is preferred when reading, debugging, or storing configuration files.
What is the maximum JSON size this formatter can handle?
Because the tool processes data in the browser, practical limits depend on the device’s available memory. Very large JSON files (tens of megabytes) may cause the browser tab to slow down or freeze. For files over a few megabytes, a command-line tool like jq is more appropriate. This formatter is optimized for the typical API response or config file size.