Fix JSON trailing comma before POST or webhook delivery
JSON does not allow a comma after the last element in an object or array. JavaScript and some config formats do, which is why copy-paste from code into APIs often breaks. Providers may reject the webhook with 400 before your handler runs.
Common causes
- Last property in an object ends with `,`.
- Last array element ends with `,`.
- Generated JSON from a tool that targets JSON5 instead of strict JSON.
How to fix
- Delete the comma after the final element.
- Paste into Request Body Validator to see the exact line and column.
- Regenerate payloads from a strict JSON serializer.
Use our tool
Validate JSON bodyRelated