Developer utility
JSON Validator
Check JSON for syntax errors and see exactly where the problem is. Validation runs locally in your browser — nothing is uploaded.
Input
Your JSON is processed locally in your browser. We don't upload your JSON to any server.
What does a JSON validator do?
A JSON validator confirms whether a string is syntactically valid JSON. When it finds a problem, a good validator points to the approximate line and column so you can fix it quickly instead of scanning the whole document by eye.
Understanding validation errors
- Unexpected end of JSON input — a value, comma or closing bracket is missing at the end.
- Expected a property name — an object key is missing its double quotes, or a colon is missing.
- Unexpected character — often a missing comma, an unquoted value, or a single quote where double quotes are required.
Use the validator together with the formatter: validate to catch errors, then format to make the result readable. Both steps happen on your device.
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