505 HTTP Version Not Supported
5xx Server error
That HTTP version is not supported.
| On the wire | HTTP/1.1 505 HTTP Version Not Supported |
|---|---|
| Code | 505 |
| Is it an error | Yes — this is an error |
| Category | 5xx Server error |
The problem is on the server side; retrying later is often worth it.
How to read this
- The first digit of a status code carries the meaning: 4 means the request, 5 means the server.
- 404 means "not there"; 403 means "there, but not for you". Swapping them makes debugging slower.
- Header names are case-insensitive — Content-Type and content-type are the same header.
- Caching and CORS problems usually come down to one header line, visible in the browser’s network tab.
Frequently asked questions
Q. What does HTTP 505 HTTP Version Not Supported mean?
That HTTP version is not supported.
Q. What does 505 HTTP Version Not Supported look like on the wire?
It travels as HTTP/1.1 505 HTTP Version Not Supported
Q. Is 505 HTTP Version Not Supported an error?
Yes. A code starting with 4 blames the request; one starting with 5 blames the server.
Q. What group does 505 HTTP Version Not Supported belong to?
The 5xx server error group; the rest of that group is listed further down.