JSON Formatter & Validator
Paste JSON to format, validate, or minify — runs entirely in your browser.
About JSON Formatter & Validator
JSON Formatter takes a raw, minified, or messy JSON string and rewrites it with consistent indentation so you can actually read it. Paste an API response, a configuration file, or a log line, and the tool re-serializes it with one value per line and properly nested braces. If the JSON is invalid, it surfaces the parser's error message — usually pointing at where the failure happened — so you can find the missing comma faster than by eye.
Beyond formatting, the tool validates and minifies. Validation confirms a document is well-formed JSON, which is worth doing before committing a config file or posting a request body. Minifying strips every space and newline to produce the most compact form possible — what you want when embedding JSON in a URL, a database column, or any payload where size counts.
To use it, paste your JSON into the input box; the formatted result appears immediately. Switch the indent option between 2 spaces, 4 spaces, or Minified to control the output, then copy the result with one click. There is no file-size limit beyond your browser's available memory, so large documents work fine.
Every operation runs locally using the browser's native JSON engine — the same parser your own code uses. Nothing is uploaded, logged, or stored, which makes the tool safe for sensitive payloads such as API keys, access tokens, personal data, and internal configuration. Close the tab and the data is gone.