Aspect Ratio Calculator
Work out the aspect ratio of any width and height, plus the new height that keeps it when you resize.
Aspect ratio1.7778
As X : 11.78: 1
New height (same ratio)720px
Aspect ratio = width ÷ height. A 1920 × 1080 image has a ratio of 1920 ÷ 1080 = 1.7778, i.e. 1.78 : 1 — the familiar 16:9. To resize while keeping that shape, scale the height with the width: new height = new width × original height ÷ original width. Rescaling 1920 × 1080 to a 1280 px width gives 1280 × 1080 ÷ 1920 = 720 px tall.
Questions
How do I calculate an aspect ratio?
Divide the width by the height. A 1920 × 1080 image gives 1.78, which is the 16:9 ratio. Multiply by a common denominator to express it as whole numbers like 16:9 or 4:3.
How do I resize without distortion?
Keep the ratio constant: new height = new width × original height ÷ original width. Scaling a 1920 × 1080 frame down to 1280 px wide makes it 720 px tall, preserving 16:9.