Aspect Ratio Calculator

Calculate aspect ratios from pixel dimensions or pick a preset like 16:9, 4:3, or 21:9. Instantly see the simplified ratio and a list of common matching resolutions - perfect for UI designers, video editors, and front-end developers.

FAQ

The calculator finds the greatest common divisor (GCD) of your width and height, then divides both by it to get the simplified ratio. For example, 1920�1080 becomes 16:9 because both divide by 120.

The tool matches your dimensions to the closest known aspect ratio (16:9, 4:3, 21:9, etc.) and lists that family's common resolutions. If no preset matches closely, it shows scaled versions of your dimensions.

16:9 (HDTV, YouTube, most monitors), 4:3 (older TVs, iPads, some photos), 1:1 (Instagram, profile pictures), 3:2 (classic 35mm photography, some laptops), 21:9 (ultrawide monitors, cinematic films). Different ratios suit different content types.

Given one dimension, divide by the ratio: for 16:9 with width=1920, height = 1920 x 9/16 = 1080. For any aspect ratio, height = width x (ratio_height / ratio_width). The calculator handles these calculations automatically.

Yes. You can enter decimal values for width and height. The calculator uses the GCD algorithm to simplify the ratio. For best results with standard screen resolutions, use whole numbers.