Favicon

A favicon is a small icon associated with a website or page. Browsers may use it in tabs, bookmarks, history, shortcuts, and other interface surfaces; some search products may also show a site's favicon beside a result. HTML pages commonly declare one or more icon resources with a `<link rel="icon">` element so the user agent can choose an appropriate format or size.

Why it matters: Use a simple, recognisable mark that remains legible at small sizes and on the backgrounds where it will appear. Provide suitable browser and device formats, declare the files correctly, return them without authentication or errors, and test fresh loads as well as cached behaviour. A missing or unusable icon falls back differently across browsers and surfaces; it is not always a globe. For Google Search, the home page and image file must be crawlable, the icon must be square and at least 8 × 8 pixels, Google recommends a size greater than 48 × 48 pixels, and the URL should remain stable. Google supports one favicon per hostname and does not guarantee display even when requirements are met.