Paste your JSON below. It will validate automatically as you type.
About this tool
This tool checks whether a block of JSON is syntactically valid as you type, and points out exactly where it breaks if it isn't. It uses your browser's own JSON parser, so the validation logic matches what your code will actually see at runtime — not a reimplementation that might behave differently.
Frequently asked questions
Why does it say my JSON is invalid when it looks fine?
The most common causes are a trailing comma after the last item, single quotes instead of double quotes, or an unquoted object key — JSON is stricter than JavaScript object literals, and all three are valid in JS but not in JSON.
Does this check JSON Schema, or just syntax?
Just syntax — whether the text parses as valid JSON at all. It doesn't validate against a schema (e.g. required fields or types), which is a separate, more specific kind of validation.