JSON Validator
Paste JSON to check whether it is valid. When it is not, the validator reports the error message and the line and column where parsing failed - all in your browser.
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About the JSON Validator
This tool checks whether a block of text is well-formed JSON according to the strict JSON grammar. When the input parses cleanly it tells you it is valid; when it does not, it surfaces the parser error along with the line and column where parsing stopped, so you can jump straight to the offending character. It is the fastest way to track down a stray comma, an unquoted key, or a mismatched bracket.
How to use it
- Paste the JSON you want to check.
- Read the valid or invalid status the tool reports.
- If invalid, use the line and column to locate the error.
- Fix the issue and re-check until it passes.
A common use is confirming a hand-edited config or API response is parseable before deploying it. Remember that valid JSON disallows comments, trailing commas, and single-quoted strings, so those will be flagged even though many languages accept them. Validation runs in your browser using the native JSON parser, so your input is never uploaded.
Frequently asked questions
What does the JSON validator check?
It checks that your text conforms to the strict JSON grammar: properly quoted keys and strings, balanced braces and brackets, valid number formats, and no trailing or missing commas.
Why does it report an error at a specific line and column?
The browser's JSON parser stops at the first character it cannot interpret. The reported line and column point to that spot, which is usually where the syntax mistake is.
Is JSON with comments considered valid?
No. Standard JSON does not permit comments or trailing commas. If your file uses them (sometimes called JSONC), it will be reported as invalid here.
Does validating my JSON send it anywhere?
No. The check is performed locally in your browser, so nothing is uploaded or stored.