Favicons and app icons (all platforms)What it checks and how to fix it

What it checks

Looks at the homepage for every kind of site icon: link rel="icon" favicons, /favicon.ico, an apple-touch-icon, the msapplication-TileImage meta tag, and the icons in the web app manifest, including the 192x192 and 512x512 sizes PWAs need. No icon at all fails; a favicon plus an Apple touch icon or both PWA sizes passes; anything less is a warning.

Why it matters

Icons are what people see in browser tabs, bookmarks, search results and home screens. A missing favicon looks unfinished, Google shows a generic globe next to the result, and iOS falls back to a blurry screenshot when the page is added to the home screen. Browsers also request /favicon.ico on every visit, so a missing one fills the logs with 404s.

How to fix it

Declare a favicon, an Apple touch icon and manifest icons in <head>:

<link rel="icon" href="/favicon.ico" sizes="32x32">
<link rel="icon" href="/icon.svg" type="image/svg+xml">
<link rel="apple-touch-icon" href="/apple-touch-icon.png" sizes="180x180">
<link rel="manifest" href="/manifest.webmanifest">
<meta name="msapplication-TileImage" content="/icon-192.png">

And list the PWA sizes in the manifest:

{
  "icons": [
    { "src": "/icon-192.png", "sizes": "192x192", "type": "image/png" },
    { "src": "/icon-512.png", "sizes": "512x512", "type": "image/png" },
    { "src": "/icon-512-maskable.png", "sizes": "512x512", "type": "image/png", "purpose": "maskable" }
  ]
}

Keep a favicon.ico at the site root as the fallback older browsers and crawlers request directly.