Icon Genie - favicon sizes

[tinohager]

At the moment the tool generates a favicon.ico which contains the following resolutions (16x16, 24x24, 32x32, 48x48, 64x64, 72x72, 96x96, 128x128, 256x256) which makes the file quite big.

• google.com has only the following sizes in their favicon.ico file. (16x16, 32x32) -> 5kb
• outlook.com has in their favicon.ico file only the following sizes. (16x16, 24x24, 32x32) -> 8kb
• quasar.dev -> 63kb

At stackoverflow also (16x16, 32x32) is recommended.

https://stackoverflow.com/questions/25952907/what-is-the-best-practice-for-creating-a-favicon-on-a-web-site

[tinohager]

https://realfavicongenerator.net/faq#why_so_many_files

Arnaud Lefort created a favicon.ico file which contains "all sizes", from 16x16 to 256x256 and checked the effects on his Windows 8.1 tablet. The results:
He also tried high resolution on MacOS with Chrome, Opera 15+, Opera 12.16, Safari, OmniWeb and iCab: none of them used a resolution higher than 32x32.

[tinohager]

also with a test tool i get this warning of an ico from icongenie

favicon.ico(4): Warning ICO240: PNG-encoded image with bit depth 3328 (expected 32).
favicon.ico(4): Warning ICO241: ICO files require the embedded PNG image to be encoded in RGBA32 format; this is Palette