Type a width and height to get its aspect ratio (1920 × 1080 is 16:9), then type a new width or height to get the other side at the same shape.
Worked out by this page:
| Size | Ratio | Used for |
|---|---|---|
1920 × 1080 | 16:9 | HD video, most screens |
1080 × 1920 | 9:16 | phone video: Reels, TikTok, Shorts |
1080 × 1350 | 4:5 | Instagram portrait posts |
1080 × 1080 | 1:1 | square posts |
1024 × 768 | 4:3 | older screens, iPad |
2560 × 1080 | 2.39:1 | ultrawide monitors |
1200 × 630 | 1.91:1 | link previews (Open Graph) |
New height = new width × height ÷ width. For 1920 × 1080 at 1280 wide: 1280 × 1080 ÷ 1920 = 720.
That’s its exact ratio; it’s close to 1.91:1, which the page shows too.
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