About the JSON Validator
The JSON Validator checks a block of JSON against the format's strict rules and tells you immediately whether it is valid. When it is not, the tool reports what went wrong and where, so you can fix a trailing comma, an unquoted key, or a stray bracket without guessing. It is an everyday helper for developers debugging API payloads, configuration files, and data exports.
Validation is performed entirely in your browser, so the JSON you check, which can include sensitive application data, never travels over the network. There is no account requirement and no usage cap. Once your JSON passes validation you can trust it will parse cleanly in your code, saving you from runtime surprises down the line.
How to use it
- 1Paste the JSON you want to validate into the input box.
- 2Run the validation to check it against JSON syntax rules.
- 3Read the result to see whether the JSON is valid or not.
- 4If invalid, jump to the reported line or position and fix the issue.
- 5Re-validate until the JSON passes cleanly.
Key features
- Instant valid or invalid verdict
- Pinpoints the location of syntax errors
- Catches common mistakes like trailing commas
- No data ever uploaded to a server
- Free and available without signup
Frequently asked questions
- What kinds of errors does it catch?
- It catches structural and syntax mistakes such as trailing commas, missing quotes, unbalanced braces, and invalid value types.
- Does validating tell me where the problem is?
- Yes. When the JSON is invalid, the validator reports the position so you can find and fix the offending character.
- Is the validator different from the formatter?
- The validator focuses on confirming correctness and reporting errors, while the formatter focuses on reshaping valid JSON for readability.
- Is my data kept private?
- Yes. Validation runs in your browser, so the JSON you paste is never sent to any server.