JSON Validator
Validate JSON syntax online with clear error messages and line numbers. Free and private.
How to use JSON Validator
- 1Paste JSON
Paste the JSON you want to validate.
- 2See results
Validation runs as you type — valid or invalid with details.
Frequently asked questions
What does the validator check?+
Strict JSON syntax per RFC 8259: matched braces, quoted keys, valid escapes, and no trailing commas.
Does this support JSON5 or comments?+
No — JSON5 and JSON-with-comments are not standard JSON and are not supported.
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