How to use the Aspect Ratio Calculator

Manually input a width and height value on the left (W1 and H1). Switch to the values on the right (W2 and H2) to see the aspect ratio value. (Ex. W1=9, H1=12 to find an 9x12 aspect ratio)

For JPG files only, use the Choose File button below and select a file on your computer. The aspect ratio calculator will put the width and height values on the left hand side for you.

Note: The value on the right can be anything you want! centimeters, inches, or pixels.


Enter the values for the original width (W1) & original height (H1) on the left, then enter either a new width (W2) or new height (H2) on the right to calculate the remaining value.
Default values are in pixels.

Change any of the values at any time, or reset them to the starting values.


Aspect Ratio: --

File Name:

File Size:

File Type:

File Width:

File Height:

An Explanation about Aspect Ratios

Understanding aspect ratios is really quite easy. Remember how to factor fractions back in middle school? Factor your width and height to the lowest common denominator and you will have your aspect ratio.

For example, if you have a painting that is 18×24 inches, then you factor 18/24 to its lowest common denominator to understand the ratio. Dividing 18/24 by 6, you get 3/4, or a 3:4 aspect ratio. If you have a 20″x30″ painting, or 20/30 = 10, which equals 2/3, this gives you have a 2:3 aspect ratio. If you want to make an 8″x10″ print from a 20″x30″ painting, you can’t do it! You can have an 8″x12″, but not an 8″x10″.