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Aspect ratio calculator
Find the matching height or width for any ratio.
Quick answer
To find an aspect ratio, type the width and height: 1920 x 1080 is 16:9. To keep a ratio when resizing, pick it, type the new width and the height is worked out for you.
How to calculate an aspect ratio
- To find a ratio, type the width and height in pixels. The simplest ratio appears below, for example 1920 x 1080 is 16:9.
- To resize to a ratio, pick one (16:9, 4:3, 1:1 and more) or type your own.
- Type the new width and the height follows, or type the height and the width follows.
The ratio is the width divided by the height, written in the smallest whole numbers. Two pictures with the same ratio have the same shape even if they have different sizes.
Heights and widths are rounded to a whole pixel. If a size is only close to a common ratio, such as 1366 x 768, the calculator says so instead of pretending it is exact.
Common questions
What is the aspect ratio of 1920 x 1080?
16:9. Divide both numbers by their greatest common divisor, 120, and you get 16 and 9.
How do I keep the ratio when I resize?
Choose the ratio, then type the new width. The height is worked out for you: height = width x ratio height / ratio width.
What is the ratio of a phone video?
Vertical phone video and stories are usually 9:16. Instagram portrait posts are 4:5.
Why is 1366 x 768 not exactly 16:9?
It is 683:384, which is within a fraction of a percent of 16:9 but not equal to it. The calculator shows both.
Does this change my picture?
No. It is a calculator and does not use any file. To resize a picture, use Resize images or Crop images with a ratio.