JSON validation is the process of checking whether a given string is valid JSON according to the specification. Our free online JSON Validator instantly checks your data for syntax errors, highlights the exact location of issues, and confirms when your JSON is well-formed.
Common JSON errors include missing commas between properties, trailing commas after the last element, unquoted keys, single quotes instead of double quotes, and mismatched brackets or braces. Our validator catches all of these and provides clear error messages.
The tool runs entirely in your browser — your data never leaves your device. Simply paste your JSON, and the validator will immediately tell you whether it is valid or highlight exactly where the problem lies.