415 Unsupported Media Type

4xx Client Error RFC 9110

Wrong content type — the server can't process what you sent.

What 415 Unsupported Media Type means {#what}

The format of the request body isn’t supported by this endpoint. Usually means a missing or wrong Content-Type header — sending XML to a JSON-only API, or forgetting application/json entirely.

When you’ll see a 415 {#when}

Missing Content-Type: application/json header
Sending multipart/form-data to an endpoint expecting JSON
Wrong encoding or media type

When to use 415 {#use}

Include the list of accepted types in the error response

Don't confuse 415

406 wrong format for the *response*, not the *request* 400 right content type, but the content itself is malformed