Web Push Notifications Creative Guidelines

Web push notifications can be enriched with images. Those fall under the names of:

Icon

The icon is a square image that is always present in the message. By default, the system will use your project logo as icon image.

Suggested dimensions	256x256 px (must be squared)
Valid image formats	PNG, JPG (JPEG), GIF
Mobile/Desktop differences	Gif animations work only on desktop
Windows (desktop)
Apple (desktop)
Android

The picture is an optional choice. It is bigger than the icon and is a great tool for marketing contents.

Suggested dimensions	512x256 px (the image can have other sizes but the ratio must be 2:1) On mobile Android will crop top and bottom of the image accordingly to the phone screen size. Therefore there is no one specific dimension, but the safe area for the content is in the middle of the image.
Valid image formats	PNG, JPG (JPEG), GIF (animated gifs work only on desktop)
Mobile/Desktop differences	Gif animations work only on desktop Different cropping ratios. On desktop, images can even be squared while Android will always crop to a ratio 2:1
Windows (desktop) & Android	Windows 10 (the notification appears in Windows notification centre) Windows (previous versions of Windows will use the standard Chrome notification) Android (the cropping of top and bottom areas depend on the phone screen size)