Why Refresh Sometimes Shows You Yesterday's Website
The useful shortcut behind web caching, and how to tell stale content from a broken connection.
You reload a page and the old picture is still there. Your friend opens the same address and sees the replacement. Neither of you is necessarily imagining things: you may be looking at different cached copies.
A shortcut with instructions
A cache stores a response so the browser or another part of the delivery system can reuse it. HTTP headers help decide whether that copy is fresh, needs checking with the server or should not be stored. The shortcut saves repeated transfers, but a badly chosen lifetime can keep an update out of sight.
Editorial image from Blogdel's technology collection, used for illustration.
Consider a restaurant changing its menu. A photograph with a new filename is easier to distinguish from the previous version than a file silently replaced at the same address. The browser cannot infer the owner's intention from the pixels it has not downloaded.
Diagnose before deleting everything
Check whether the problem affects one page or many. Try a fresh visit in a separate browsing context. If only one asset stays old, the site may need to change its caching instructions or version that asset.
Clearing all browser data is a blunt tool: it can sign you out without fixing a server cache. Report the exact address and what differs. That gives the person maintaining the website something more useful than “the internet is broken.”
Editorial image from Blogdel's technology collection, used for illustration.
Sources and further reading
References
- HTTP caching | Mozilla · primary