HTTP headers
Expires HTTP Header Meaning
Expires gives an absolute time when a response becomes stale.
Meaning
The server is using an HTTP date to define cache freshness.
Where it appears
Older cache setups and static asset responses may include it, often alongside Cache-Control.
What to check
Check Cache-Control first; it usually overrides Expires when both are present.
Example
Expires: Wed, 21 Oct 2026 07:28:00 GMTReferences
- Registry
- IANA HTTP Field Name Registry
- Guide
- MDN Expires