Format, validate, and beautify JSON data. Minify or pretty-print with customizable indentation.
Instant beautification
JSON Formatter validates and beautifies your JSON data. It supports both formatting (pretty-print) and minifying. Formatting is lossless: large 64-bit integers keep their exact value (no 2^53 precision loss), and syntax errors point at the exact line and column. All processing happens locally in your browser - your data is never sent to any server.
The JSON Formatter takes raw, minified, or messy JSON and instantly reformats it into clean, properly indented, human-readable text — while validating that the structure is correct as it goes. Reach for it when an API response, config file, or log entry arrives as one unreadable line, or when you need to confirm whether a snippet of JSON is actually valid before pasting it into your code. Everything runs entirely in your browser, so the data you paste never leaves your machine.
It re-indents and spaces out JSON so the nested structure is easy to read, and validates the syntax at the same time. A single-line, minified blob becomes a clean, properly aligned document, and you immediately learn whether the JSON is well-formed.
Yes. The formatter runs 100% in your browser. Your JSON is processed locally and is never uploaded, sent to a server, stored, or tracked, so you can safely paste API responses or config data that contain sensitive values.
Yes, it is completely free with no sign-up required, and you can use it as often as you like.
The tool validates as it formats. If the JSON parses cleanly you get the beautified output; if it does not, it flags the input as invalid so you can locate and fix problems like a trailing comma, an unquoted key, or an unmatched bracket.
JSON is strict: keys and strings need double quotes, no trailing commas are allowed after the last item, and brackets and braces must be balanced. The validator catches these so you can correct the source.
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