How to work out an aspect ratio, and resize without stretching.
How to find the aspect ratio of a picture or screen from its pixels, why 1366 × 768 is not quite 16:9, and how to work out a new size that keeps the shape.
By Suraj Kumar4 min read
A picture's aspect ratio is its width to its height in smallest whole numbers. It decides whether it fits a screen or a post without bars or cropping.
Simplify the width and height.
1920 × 1080 divides by 120 to give 16 : 9. The Aspect ratio calculator does this and names the common shapes: 16:9 for video and most screens, 9:16 for Reels, Shorts and Stories, 4:5 for portrait posts and 1:1 for square ones.
Sizes that are nearly a common shape.
1366 × 768 simplifies to 683 : 384, which is within 0.1% of 16:9 but not exactly it. The page gives the exact ratio and says which common shape it is close to and how close.
A new size that keeps the shape.
Give a new width and the height is the old height times the new width over the old width: 1920 × 1080 at 1,280 wide is 1,280 × 720. Sizes that do not come out whole are rounded and the page says so, and it warns when a video would want an even number. To change a picture or crop a video, the image resizer and the video editor do it on your device.
Further reading
Topics: aspect ratio calculator · aspect ratio · 16:9 · 1920x1080 aspect ratio · resize keep aspect ratio · 9:16
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