Developer & Data Tools

JSON Validator

Check whether text is valid JSON and see the parser error if it is not.

Runs in your browser Your input never leaves your device.

0 characters | 0 words

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About this tool

Paste JSON to check whether it is valid. The tool runs your text through the browser's JSON parser and tells you "Valid JSON" or shows the error message. It does not reformat or fix the data; use the JSON beautifier for that. Checking happens in your browser as you type and nothing is uploaded. The wording and position details of error messages come from your browser, so they can differ between Chrome, Firefox and Safari.

How to use it

Paste your JSON into the box.
Read the verdict below.
If it is invalid, use the error message to find the problem and edit your text.

Example

Input

{"name":"Ada","age":36}

Result

✓ Valid JSON.

Common problems

Trailing comma error: JSON does not allow a comma after the last item in an object or array. Remove it.
Single quotes or unquoted keys: Strict JSON needs double quotes around keys and strings. {'a': 1} and {a: 1} are invalid.
Comments or special values: JSON has no comments, and values like undefined or NaN are not allowed. Remove them or use null.