JSON Formatter & Validator
Format, minify and validate JSON free online.
How to use this tool
Paste JSON
Drop your JSON into the editor — or load the sample to try it.
Format or minify
Pretty-print with your indent style, or squeeze it down for production.
Copy or download
Copy the result or download it as a .json file.
Frequently asked questions
How do I know where my JSON error is?
Click Validate or Format — the tool reports the exact line and column of the first syntax error, so you can jump straight to it.
Is my JSON data uploaded anywhere?
No. Parsing and formatting happen entirely in your browser with JavaScript. Nothing you paste ever leaves your device.
What's the difference between Format and Minify?
Format pretty-prints with indentation for readability. Minify strips all unnecessary whitespace for the smallest possible file size — ideal before sending data over the network.
Is there a size limit?
The amount of input this tool can handle depends on available browser memory and the limits shown by the controls. Larger jobs can take longer or fail; try a smaller input if the page becomes slow.
Does it support JSON5 or comments?
No — this is a strict JSON formatter. Comments and trailing commas are not valid JSON and will be flagged as errors.