Check whether text is valid JSON and, when it is not, read a plain explanation of the first error.
Try an example
Load a ready-made sample into this tool and run it. Every result you see is calculated live by the tool itself — nothing here is a pre-written answer.
Sample: input: {"name":"Manage My Tools","free":true}
How to Use
- Paste the text to check.
- Click Run.
- Fix the reported problem and validate again.
What this JSON validator does
This JSON validator checks whether a piece of text is valid JSON — whether its brackets, commas, quotes and values follow the rules of the format. When the text fails, you do not just get a yes or no: the validator explains the first error it finds in plain words, so you know what to fix and roughly where to look.
How the checking works
Paste the text, run the check, and read the verdict. Validation is a syntax reading, done the same way a program would parse the data, which makes it a reliable first step when an API rejects a payload or a config file refuses to load. Fix the reported error and validate again, since one slip often hides the next.
Good to know
Validation checks syntax only — not meaning. This is not JSON Schema checking: the validator cannot tell whether required fields are present, whether values are the right type, or whether the data itself is correct or complete. A file can pass here and still be wrong for your application.
Frequently asked questions
What kinds of errors does it find?
The structural ones: missing or extra commas, unclosed brackets and braces, unquoted keys, single quotes where double quotes belong, and values the format does not allow. The explanation names the first problem found; later ones appear after you fix it.
Does passing mean my data is correct?
No. Passing means the text is well-formed JSON that a program can read. It says nothing about whether the fields, values or contents are right. Think of it as a spelling check for structure, not a review of the facts.
Why does it report only the first error?
A parser cannot trust anything after the point where the structure breaks, so the first error is the only one it can locate reliably. Correct that one and run the check again; the next problem, if any, will be reported then.
How to use JSON Validator
- Paste the text to check.
- Click Run.
- Fix the reported problem and validate again.
Limitations
Validation checks syntax only; it cannot tell whether the data itself is correct or complete.