Picking a video size that fits where you're posting
Every place you post video wants a different shape.
| Shape | Pixels | Where it's used |
|---|---|---|
| Vertical, 9:16 | 1080×1920 | Reels, Shorts, anywhere someone's holding their phone upright |
| Square, 1:1 | 1080×1080 | Feed grids, where posts sit side by side |
| Landscape, 16:9 | 1920×1080 | Long-form YouTube, anything watched on a computer screen |
Drop a 9:16 clip into a Reels or Shorts slot and it fills the screen edge to edge, no bars. Drop a 16:9 clip into that same slot and there's empty space on the sides, or the top and bottom get cropped off. The 1080p ceiling on Shorts is official: it's the number in YouTube's own help pages. Reels and TikTok land on 1080×1920 too, though neither platform has put that figure in writing anywhere. It's the number that keeps turning up once enough sources get compared, closer to a convention than a published rule.
Screen recordings default to landscape
Record a screen on a computer, whether it's one window or the whole desktop, and the result usually comes out around 16:9: wide, not tall. Drop that straight into a Reels or Shorts slot and there's a lot of empty space top and bottom. Footage shot the other way, holding a phone upright, comes out 9:16, so that one leaves gaps on the sides if it lands in a landscape slot instead.
Deciding the shape before hitting record is the cleanest fix. A screen recording headed for Reels goes more smoothly if the window gets narrowed toward vertical first, or gets cropped to portrait in an editor beforehand. Either one means less work later.