Aspect Ratio Calculator
Reduce an image ratio and calculate a matching height for a new width.
How to use the aspect ratio calculator
Enter whole-pixel width and height to reduce an image ratio. An optional new width gives the proportional height.
Example
A 1920 by 1080 image is 16:9; at 1280 pixels wide its matching height is 720.
Good to know
Rounding to a whole pixel may change the exact ratio by a tiny amount.