Aspect ratio calculator
An aspect ratio is width over height, reduced to the smallest whole numbers. Enter the original dimensions and one of the new ones, and the other follows.
The result is rounded to whole pixels, so the ratio can come out a fraction of a percent off the original. For video, codecs often require dimensions divisible by two or four.
Frequently asked questions
What ratio does a typical screen use?
16:9 for most monitors and televisions, 16:10 for many laptops, 21:9 for ultrawide, 4:3 for older material and 9:16 for vertical video.
Why do black bars appear?
Because the material has a different ratio from the screen. The player keeps the original ratio and fills the rest with black rather than distorting the picture.
What size should a social image be?
1200×630 for a link preview, about 1.91:1. A 1080×1080 square and a 1080×1350 portrait cover most of the rest.