通常faviconというと、16×16 / 32×32のicoファイルを指定するのみですが、最近はスマートフォンなどの表示に合わせて複数のfaviconを指定する動きが見られます。
その際のfaviconは、それぞれに合わせたサイズのpngファイルを作成してヘッダーにタグを埋め込みます。
- 16px: For general use in all browsers, could be displayed in the address bar, tabs or bookmarks views!
- 24px: Pinned Site in Internet Explorer 9
- 32px: New tab page in Internet Explorer, taskbar button in Windows 7+ and Safari’s ‘Read Later’ sidebar
- 57px: Standard iOS home screen (iPod Touch, iPhone first generation to 3G)
- 72px: iPad home screen icon
- 96px: GoogleTV platform
- 114px: iPhone 4+ home screen icon (twice the standard size for the retina display)
- 128px: Chrome Web Store
- 195px: Opera Speed Dial
<link rel="icon" sizes="16x16 32x32" href="favicon.ico"> <!--[if IE]><link rel="shortcut icon" href="favicon.ico"><![endif]--> <!-- For iPad with high-resolution Retina display running iOS ≥ 7: --> <link rel="apple-touch-icon-precomposed" sizes="152x152" href="favicon-152.webp"> <!-- For iPad with high-resolution Retina display running iOS ≤ 6: --> <link rel="apple-touch-icon-precomposed" sizes="144x144" href="favicon-144.webp"> <!-- For iPhone with high-resolution Retina display running iOS ≥ 7: --> <link rel="apple-touch-icon-precomposed" sizes="120x120" href="favicon-120.webp"> <!-- For iPhone with high-resolution Retina display running iOS ≤ 6: --> <link rel="apple-touch-icon-precomposed" sizes="114x114" href="favicon-114.webp"> <!-- For first- and second-generation iPad: --> <link rel="apple-touch-icon-precomposed" sizes="72x72" href="favicon-72.webp"> <!-- For non-Retina iPhone, iPod Touch, and Android 2.1+ devices: --> <link rel="apple-touch-icon-precomposed" href="favicon-57.webp">