The pixel ratio is the ratio of the pixel's width to its height. If the pixels are square, the pixel ratio is 1 and the number of pixels in X divided by the number of pixels in y equals the aspect ratio.
Pixel_Ratio = Pixel_Width / Pixel_Height
X_Resolution / Y_Resolution = Aspect_Ratio / Pixel_Ratio
See Aspect Ratio
The Game Dictionary™ is a trademark of GameDev.net LLC. No duplication, reproduction, or transmission of the Game Dictionary or its content is allowed without the consent of GameDev.net LLC.