426Upgrade Required
The server refuses this request on the current protocol and tells you which one to switch to.
Browse all HTTP status codesWhen you see it
A server that requires a newer protocol version answers 426 with an Upgrade header naming what it wants. It is uncommon on the public web, where servers usually redirect rather than refuse.
The clearest real use is an API that has withdrawn support for an outdated encryption version. Rather than letting an insecure connection succeed, it refuses and names the version that would work.
Look up another one
Open
Type a code, a partial code like 40, or any word from a name or description. Everything runs in your browser.
Filter
Copy format
Status codes
69 of 69 codes. Click a row to copy it.
1xx Informational (4)
2xx Success (10)
3xx Redirection (8)
4xx Client errors (31)
5xx Server errors (16)