JSON Formatter

Frequently asked questions

Can I format more than one JSON file at once?

Yes. Switch to Batch - multiple files, then drop or choose several files. Each one is processed in your browser, and the results can be downloaded together as a .zip. When we tested it, 40 files were processed in 0.2 seconds and packed into the .zip in 0.4 seconds.

Is my JSON uploaded to a server?

No. Every operation runs as JavaScript on your own device. We watched the network activity while formatting and while building the .zip: the page sent nothing to any third party.

Is there a file size limit?

We do not set one. In our test a single 5 MB file was formatted in 47.6 seconds in this browser. Whether larger files work depends on how much memory your device has, so we do not promise a number we have not measured.

Can I convert JSON to CSV?

Yes, when the JSON is an array of objects or a single object. Columns are written in first-seen order, nested objects and arrays are kept as JSON text inside their cell, and a UTF-8 BOM is added so Excel reads accented and CJK characters correctly. If the JSON cannot be tabulated, the page says so instead of writing a file that looks fine but means something else.

Can I merge several JSON files into one?

Yes. In batch mode choose Merge into one JSON file. If every file holds an array, those arrays are joined into one array. If they do not all hold arrays, each file becomes one element of the output array. Either way the status line tells you which rule was applied.

What happens if my JSON is invalid?

The page reports the line and column, shows the offending line with a caret pointing at the problem, and quotes the parser's reason. In batch mode a file that fails is listed as Invalid and left out of the download, while the rest still go through.

Do I need an account, and is there a usage limit?

No account, no sign-up, no watermark. There is no server counting your requests, so there is no usage limit to hit.