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JSON Formatter and Beautifier

Paste messy or minified JSON and get clean, indented, readable JSON — with the exact line and column of any syntax error.

Runs in your browser. Nothing you type is sent to a server.

How to use JSON Formatter & Beautifier — Free Online JSON Pretty Print

  1. 1Paste your JSON into the left-hand box.
  2. 2Pick your indent size, and optionally sort the keys alphabetically.
  3. 3Copy the result, or download it as a file.

About JSON Formatter

JSON is easy for machines to read and painful for people when it arrives as one long line. This formatter parses the document and prints it back with real indentation, so nesting becomes visible and you can find the field you actually care about.

The error reporting is the part worth having. A browser's built-in parser reports something like "Unexpected token } in JSON at position 1184", which tells you nothing useful in a 2,000-character string. This tool converts that offset into a line and column number and shows you the offending line, so a missing comma takes seconds to find instead of minutes.

Sorting keys alphabetically is handy before a comparison: run both documents through with sorting on, and a diff then shows only genuine value changes rather than reordering noise.

Frequently asked questions

What does a JSON formatter actually do?
It parses your JSON and prints it again with consistent indentation and line breaks. The data is identical — only the whitespace changes — so a formatted file and a minified file mean exactly the same thing to any program that reads them.
Why does it say my JSON is invalid?
The most common causes are a trailing comma after the last item, single quotes instead of double quotes, unquoted keys, or a missing closing brace. This tool shows the line and column so you can jump straight to it.
Can it handle very large JSON files?
Yes, within your browser's memory. Files of a few megabytes format instantly; very large files may take a moment because the whole document is parsed at once.
What does sorting keys do?
It reorders every object's keys alphabetically, all the way down. That makes two versions of the same document easy to compare by eye, and the meaning is unchanged because JSON objects are unordered by definition.
Is my data sent to a server?
No. The whole tool is JavaScript running on your own device, so your text never leaves the browser. You can load the page, go offline, and it still works.
Is it free?
Yes — unlimited use, no sign-up, no watermark and no limit on how many times you run it.