A favicon is the small icon that shows up in a browser tab, a bookmark list, or a phone's home screen shortcut. It's often the smallest, most overlooked piece of a website's branding — and also one of the least forgiving, because it gets displayed as small as 16 by 16 pixels. A logo that looks sharp and detailed at normal size can turn into an unreadable smudge at that scale.

Design for the smallest size first

The easiest way to end up with a bad favicon is to design a full logo, then shrink it down and hope for the best. Fine detail, thin lines, and small text all disappear at 16px. Instead, think about what the simplest, most recognizable version of your mark is — often just an initial, a simple geometric shape, or a single bold icon — and design that first, checking how it looks at genuinely tiny size before finalizing anything.

A few concrete guidelines

From design to actual file

Once you have a simple, square PNG that reads clearly at small size, it needs to become an actual .ico file — the format most browsers and operating systems specifically look for, even though many now also accept a plain PNG. A proper favicon.ico file bundles several sizes together (commonly 16, 32, 48, 64, 128, and 256px) so the browser or OS can pick whichever fits the context it's displaying the icon in.

You can generate that bundled file directly from a single square PNG — this tool resizes your image to all six standard sizes and packages them into one favicon.ico automatically.

Putting it on your site

Drop the resulting favicon.ico file at the root of your site (so it's reachable at yoursite.com/favicon.ico) — most browsers check that location automatically. For more control, add this line inside your HTML's <head> section:

<link rel="icon" href="/favicon.ico">

Have a square logo ready? Generate your favicon.ico →