101 Switching Protocols
1xx Informational
The connection is switching protocol — this is how a WebSocket begins.
| On the wire | HTTP/1.1 101 Switching Protocols |
|---|---|
| Code | 101 |
| Is it an error | No — not an error |
| Category | 1xx Informational |
A progress note; the real answer follows.
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 101 Switching Protocols mean?
The connection is switching protocol — this is how a WebSocket begins.
Q. What does 101 Switching Protocols look like on the wire?
It travels as HTTP/1.1 101 Switching Protocols
Q. Is 101 Switching Protocols an error?
No — it is part of a normal exchange, not a failure.
Q. What group does 101 Switching Protocols belong to?
The 1xx informational group; the rest of that group is listed further down.