Favicons Explained

A favicon is the small icon shown in a browser tab, bookmark list and history entry for a site. Browsers look for it in one of two ways: a link tag in the page's head with rel="icon" pointing at an image, or, if no such tag exists, a request straight to /favicon.ico at the site's root as a fallback convention dating back to the earliest browsers.

A generic globe or blank icon almost always means neither of those two things resolved successfully: no link tag was found, and nothing exists at /favicon.ico either, or what does exist there is not actually a valid image. This is an easy thing to miss after a redesign or a migration to a new host, since the rest of the page can look completely fine while the favicon quietly stops loading.

Browsers cache favicons more aggressively than most other assets, specifically because they rarely change and re-fetching one for every tab would be wasteful. This means a genuinely fixed favicon can still show the old one in a browser that already cached it, sometimes for days, which is worth ruling out before assuming a fix did not work.

A single favicon.ico file is enough for a browser tab, but modern operating systems ask for larger, differently formatted icons for things like a phone's home screen or a browser's pinned tab feature. Most real sites today declare several icon link tags at different sizes rather than relying on the single legacy fallback alone.

Favicon Checker looks for a declared icon link tag, falls back to the conventional /favicon.ico location if none is found, and confirms whether whatever it finds actually loads. Run it after a redesign or a host migration specifically, since those are the two situations most likely to quietly break a favicon without anything else on the page looking wrong.