Aspect Ratio Calculator

Calculate the aspect ratio of any dimensions and scale resolutions proportionally.

Aspect Ratio Calculator computes the simplified ratio for any width and height pair, and scales dimensions proportionally — given a target width, it calculates the matching height that maintains the original aspect ratio. It works in both directions: enter dimensions to get the ratio, or enter a ratio and a target width to get the matching height. Common ratios (16:9, 4:3, 1:1, 21:9, 9:16, 2:3) are available as quick-pick shortcuts. Designers use it to generate responsive image sizes, calculate video player dimensions, set thumbnail crops, and verify that exported assets have the correct proportions. Developers use it to implement responsive layouts, calculate CSS padding hacks for aspect-ratio boxes, and size canvas elements. Video editors use it to convert between standard resolutions while maintaining widescreen or portrait ratios.

How Aspect Ratio Calculator works

Aspect Ratio Calculator is a free browser-based utility from Salah Tools Hub. It is designed to give you an immediate result without an account, subscription, or upload to a remote server.

Enter your information into the tool after the page loads, review the result, and use the available copy or download controls. Your input stays on your device while the tool is running.