415
Unsupported Media Type
The server refuses the request because the Content-Type header specifies a media type that the endpoint does not support. The payload format is not one the server is willing to accept.
What does HTTP 415 mean?
The server refuses the request because the Content-Type header specifies a media type that the endpoint does not support. The payload format is not one the server is willing to accept.
Common causes
- 1
Sending JSON to an endpoint that expects form data (application/x-www-form-urlencoded), or vice versa.
- 2
Missing Content-Type header entirely. Some frameworks default to a type the endpoint does not accept.
- 3
Uploading a file type the server does not support (e.g., sending a .webp image to an endpoint that only accepts .jpg and .png).
How to fix it
- 1
Set the correct Content-Type header: application/json for JSON, multipart/form-data for file uploads, application/x-www-form-urlencoded for form data.
- 2
Check the API documentation for accepted media types. The response may include an Accept header listing supported types.
- 3
If using fetch or axios, ensure the Content-Type is not being overridden by default settings or interceptors.
Monitor for HTTP 415 errors
A 415 on a previously working endpoint usually means a deployment changed the accepted content types. Uptrack monitors response codes so you catch these breaking changes quickly.
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