How to Validate JSON and Find Common Errors
Learn the most common JSON syntax errors and a quick workflow for checking whether JSON is valid before using it in an application.
Check quotation marks
JSON property names and string values use double quotes. Smart quotes and unquoted keys can cause validation errors.
Check commas
Items in objects and arrays are separated by commas. A missing comma or an extra trailing comma can make JSON invalid.
Match brackets
Every opening brace or bracket must have the correct closing character. Nested structures should close in the correct order.
Check values
Valid JSON values include strings, numbers, true, false, null, objects, and arrays.
Validate before debugging code
If an API payload or configuration file is rejected, validate the JSON first. This separates a syntax problem from an application problem.
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