Size matters. Now that we have your attention. Let's clarify. We are talking about video. More specifically, the best video shapes and sizes for different platforms. Let's start out with the basics. The three most common sizes are: Widescreen (16:9), Square (1:1), and Vertical (9:16). Yes. Vertical. Vertical Video is no longer the black sheep. Indeed there was a time when shooting vertical video was frowned upon.