Aspect Ratio Calculator
Simplifies a width and height to their aspect ratio.
Aspect ratio
—
Share sends a link that reopens these numbers. Copy details pastes the full breakdown as a list.
As a decimal — : 1
Nearest common ratio —
Difference from it — %
The formula
ratio = width ÷ gcd : height ÷ gcd
Dividing both sides by their greatest common divisor gives the simplest whole-number ratio. Sizes are rounded to whole pixels first.
What to watch out for
Many sizes marketed as 21:9 are not exactly that, which is why the nearest common ratio is shown as well.
Frequently Asked Questions
What is the aspect ratio of 1920 × 1080?
16:9.
Is 2560 × 1080 really 21:9?
Not quite. It simplifies to 64:27, which is 1.6% away.