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JSON Formatter

Format, minify and validate JSON, with the exact line of any error

Output Style

About JSON Formatter

The JSON Formatter pretty-prints or minifies JSON, and when the parser rejects it, points at the line and column that broke and prints that line with a caret under the offending character. Built for debugging API responses and config files where the error is somewhere in 300 lines you didn't write.

FreeNo paywalls or tiers
No SignupNothing to create
InstantNo setup, no install
Any DeviceMobile, tablet, desktop

The guide behind this tool

JSON Errors Explained: Trailing Commas, NaN and Other Rejections

Why valid-looking JSON fails to parse, how to read a parser's error position, and the number precision bug that silently corrupts large IDs.

8 min read

How to use JSON Formatter

  1. 1

    Paste your JSON, or drop a .json file straight onto the input box.

  2. 2

    Choose Format with 2 spaces, 4 spaces or tabs, or switch to Minify to strip every byte of whitespace.

  3. 3

    Copy or download the result, or follow the caret to the character that broke the parse.

Frequently Asked Questions

You get the line and column, plus the line itself with a caret under the exact character, instead of just "Unexpected token at position 412". Long or minified lines are windowed around the error so the caret stays on screen.