Free JSON Validator Online
Use this free JSON validator to check JSON syntax and find errors. Fast, private, and works directly in your browser.
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What is JSON Validator?
JSON Validator checks whether your JSON is valid and points to the line and position of any syntax error. It is useful for debugging API payloads and config files. Validation runs in your browser, so your data stays private.
How to use this tool
- Paste your JSON into the input box.
- See whether it is valid.
- Fix any error shown with its location.
Features
- Check JSON validity instantly
- Clear error message with position
- Shows a success state for valid JSON
- Works with large JSON
- Runs entirely in your browser
This tool runs in your browser. Your files and text are not uploaded to our servers, and we do not store your input.
Frequently asked questions
Does it tell me where the error is?+
Yes. It reports the error message and the approximate position in your JSON.
Is my JSON uploaded?+
No. Validation happens entirely in your browser.
What counts as valid JSON?+
Strict JSON: double-quoted keys, no trailing commas, and no comments.
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