What aspect ratio should YouTube Shorts be?

9:16 vertical, ideally 1080x1920. Anything squarer gets pillarboxed with black bars, which reads as unfinished in a feed.

The ratio is the easy part. What catches people out is the safe zone: platform UI covers roughly the bottom 15% and part of the right edge, so captions or text placed there sit behind the title, channel name and buttons.

Those margins differ slightly between YouTube, TikTok and Reels. If you cross-post, compose for the most aggressive of the three rather than adjusting per platform.

Leaxor exports 1080x1920 with captions inside the safe zone on all three, so one file works everywhere without repositioning.