JSON Validator
Check whether your JSON is valid and see a friendly error message if not, instantly in your browser.
How to use the JSON Validator
- Paste the JSON you want to check.
- Click Run.
- If it's invalid, read the error message and position, fix the problem and run again.
How the JSON Validator works
The validator runs your input through the browser's strict JSON parser, which follows the JSON standard (RFC 8259). If parsing succeeds, the JSON is valid. If it fails, you see the parser's message, which usually includes the position of the first error.
The most common errors are trailing commas after the last item, single quotes instead of double quotes, unquoted keys, comments (not allowed in JSON) and missing commas between items. Once it's valid, tidy it up with the JSON Formatter.
Frequently asked questions
- Is this tool free?
- Yes. Validate JSON at no cost, with no account required.
- Does it tell me where the error is?
- Yes, where possible. The browser's JSON parser reports the position of the first syntax error it finds.
- Does this check against a JSON Schema?
- No. It checks that the JSON is syntactically valid, not that it matches a particular schema or structure.
- Does my text leave my browser?
- No. The conversion runs entirely in your browser, so your text is never sent to a server.