Server-Timing
Response headers
Reports how long each stage inside the server took.
| On the wire | Server-Timing: … |
|---|---|
| Category | Response headers |
Headers the server attaches when it answers.
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 Server-Timing mean?
Reports how long each stage inside the server took.
Q. What does Server-Timing look like on the wire?
It travels as Server-Timing: …
Q. Where does Server-Timing appear?
In response headers.
Q. What group does Server-Timing belong to?
The response headers group; the rest of that group is listed further down.