Aspect Ratio Calculator
Simplify any width and height into its lowest-terms aspect ratio, with common names like 16:9 recognised.
Quick answer: enter your details below and click Calculate — your result appears instantly, right here in your browser. Nothing you enter is uploaded or stored.
A
Calculators
Enter your details below.
How to use
- Enter the width in pixels or any unit.
- Enter the height in the same unit.
- Press Calculate to see the simplified ratio and its common name if it has one.
About this tool
The calculator divides both dimensions by their greatest common divisor to reduce the ratio to its simplest form. It then checks the result against well-known ratios: 16:9, 4:3, 21:9 and 1:1, and labels anything else as custom.
Frequently asked questions
Do width and height need to be in pixels?
No. Any consistent unit works, since only the relationship between the two numbers matters.
What does a custom ratio mean?
It simply means the simplified ratio is not one of the famous ones listed. It is still a valid aspect ratio, just less common.