What this tool checks
It parses your text with the standard JSON parser, so it accepts exactly what JSON.parse accepts. If parsing fails you get the parser's message, which usually points to the position of the problem.
Common JSON errors
- Trailing commas after the last item in an object or array.
- Single quotes instead of double quotes around strings and keys.
- Unquoted keys such as
{name: 1}. - Comments, which JSON does not allow.
Privacy
Parsing and formatting happen locally in your browser, so you can safely paste configuration or API responses. Avoid pasting secrets into any website you do not control as a matter of habit.