Why validation matters
A lot of broken requests come down to one comma, quote, or bracket in the wrong place.
Catching that early is easier than discovering it later through a failed deploy or a vague API error.
Yes. It is free to use, and it runs right in the browser.
No. Your JSON stays in the page. Formatting, validation, comparison, and conversion all happen locally.
Most failures come from missing quotes, comments, trailing commas, or broken nesting.
No. It just checks whether the parser can read it.
A lot of broken requests come down to one comma, quote, or bracket in the wrong place.
Catching that early is easier than discovering it later through a failed deploy or a vague API error.
Single quotes, comments, trailing commas, and `undefined` are fine in some JavaScript contexts but not in JSON.
If the data came from code, serialize the object properly instead of pasting a JavaScript literal into a JSON file.
These pages are meant to stay direct: input at the top, results immediately below, then the FAQ and related guides if you need more context.