JSON Validator
Paste JSON and instantly find out whether it's valid, with a clear explanation when it isn't.
The JSON Validator checks whether a piece of text is syntactically valid JSON — without reformatting or altering the content, just confirming whether it can be parsed correctly.
Your files are processed locally in your browser and are not uploaded.
How to use JSON Validator
- 1
Paste your JSON
Into the input field.
- 2
Click "Validate"
- 3
See the result
Valid, or an error message pointing to the problem.
Validating isn't the same as formatting
This tool only checks syntax — it doesn't re-indent or fix the JSON. To reformat already-valid JSON, use the JSON Formatter.
What the error message tells you
When the JSON isn't valid, the tool shows the error message produced by the browser's own parser, which usually points to where the syntax broke — a stray comma, unclosed quotes, and so on.
When should you use this tool?
Developers
Check whether a JSON pasted from an API or log is valid before using it.
Debugging
Quickly figure out whether an error is coming from malformed JSON.
Configuration
Check a config file before saving it.
Frequently asked questions
- Does this check my JSON against a schema?
- No, it only checks that the JSON is syntactically valid, not that it matches a specific schema.