408 Request Timeout

4xx Client error

The server waited and the request never finished arriving.

On the wireHTTP/1.1 408 Request Timeout
Code408
Is it an errorYes — this is an error
Category4xx Client error

The problem is on the request side; sending the same thing again will fail again.

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 408 Request Timeout mean?

The server waited and the request never finished arriving.

Q. What does 408 Request Timeout look like on the wire?

It travels as HTTP/1.1 408 Request Timeout

Q. Is 408 Request Timeout an error?

Yes. A code starting with 4 blames the request; one starting with 5 blames the server.

Q. What group does 408 Request Timeout belong to?

The 4xx client error group; the rest of that group is listed further down.

Same group

Reference docs