JSON Validator
Check whether a JSON string is well-formed, and see the exact line and column of any syntax error.
How it works
- 1
Paste the JSON you want to check into the input area.
- 2
The result updates instantly — green for valid, red for invalid.
- 3
If there is an error, the exact line and column are shown so you can jump straight to it.
Questions
What counts as valid JSON?
JSON must follow RFC 8259: one top-level value (object, array, string, number, boolean, or null), quoted keys, no trailing commas, and no JavaScript comments.
Why does the tool show a line and column?
The browser's JSON parser reports where it stopped, making it faster to find and fix the mistake.
Is my JSON uploaded anywhere?
No. Validation runs entirely inside your browser; nothing is sent over the network.
Can I validate a very large JSON file?
Yes, though very large inputs may take a moment. Paste the text directly or use the file drop zone if one appears.
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