JSON Validator
Check whether JSON is valid. Errors show the line, the column and the likely cause, such as a missing comma or single quotes.
Free · No upload · 100% on your device
How to use JSON Validator
- Type or paste your code or data, or open a file.
- The result updates as you type.
- Copy the result or download it as a file.
Private by design. Everything you type, open or record is processed in this browser tab and is never uploaded to KittySuite.
About JSON Validator
The browser’s own JSON parser checks the text against the JSON standard, so the result matches what JavaScript, APIs and most languages accept. Comments and trailing commas are not part of JSON and are reported as errors.
Everything runs in this browser tab: your text is never uploaded or stored, and the result updates as you type. It keeps working offline once the page has loaded.
JSON Validator: frequently asked questions
How do I check if my JSON is valid?
Paste it and the result shows whether it is valid. Errors give the line, the column and the likely cause.
Why are comments and trailing commas reported as errors?
They are not part of the JSON standard. The browser’s own parser is used, so the result matches what JavaScript, APIs and most languages accept.
Does it check my data against a schema?
No. It checks that the text is valid JSON, not that it has particular fields or types.
How do I fix single quotes?
JSON needs double quotes around keys and strings. Replace them and validate again.