Readable JSON is easier to review, debug, compare, and share. A good JSON formatter should make structure visible while also telling you when the input is not valid JSON.
Format first, then validate
Paste the JSON response, configuration file, or request body into the formatter. Pretty-printing makes nested objects and arrays easier to inspect, while validation catches missing quotes, trailing commas, and mismatched brackets.
If the formatted result cannot be produced, start with the first reported error and inspect the characters immediately before it. JSON errors are often caused by one small syntax issue earlier in the document.
When to minify JSON
Minified JSON removes whitespace and is useful when you need a compact request body, fixture, or data URL. Keep a formatted copy for review and debugging; minification makes manual inspection harder.
Keep sensitive JSON private
For tokens, configuration files, and customer data, prefer a tool that processes the input locally. Review the page notice before pasting production values.