Aspect Ratio Calculator

Height720
Ratio16:9 (1.78:1)
Calculated locally in your browser. Your input stays only on this page.

Resize while keeping the same ratio

Enter an original width and height to fix the aspect ratio, then type a new width to get the matching height — or switch the toggle to enter a new height and get the width. The simplified integer ratio (such as 16:9) and its decimal form update live. Decimals and large values are supported; a zero, negative, or non-numeric original has no defined ratio and shows an inline error.