HTTP headers / response header
Expires: Thu, 12 Jun 2026 08:00:00 GMT
Legacy absolute-time cache expiry. Cache-Control: max-age wins whenever both are present.
Clock skew makes absolute dates fragile — treat Expires as the fallback for ancient caches, not the policy.
The fastest way to see what Expires is actually doing is to send the request and read both sides raw — ReqPad shows auto-generated and custom headers for every request, on all six protocols, with history. Related references: status codes · WWW-Authenticate · Content-Encoding · Transfer-Encoding · ETag · Last-Modified · Location
Build the request, send it, read raw headers and timing — from your iPhone. Free to start.