The ad formats used on Facebooks are the same as those present on Instagram:
The 1:1 ratio format with a resolution of 1080×1080 pixels
The 9:16 ratio format for the video in stories or real with a resolution of 1080×1920 pixels
In feed the video format is displayed with a resolution of 1080×1350 pixels and then on click in 1080×1920, but also in 16:9 ratio with a landscape format with a resolution of 1920×1080 pixels