Aspect Ratio Calculator

Aspect ratio is the proportional relationship between an image's width and height, expressed as two numbers separated by a colon (e.g., 16:9). It describes the shape of an image or video without specifying its actual size.

16:9 is the most common aspect ratio for video content, TVs, monitors, and YouTube. For photography, 3:2 (used by most DSLR cameras) and 4:3 (used by many phones and older displays) are also very popular.

To calculate aspect ratio, divide both the width and height by their greatest common divisor (GCD). For example, 1920÷120=16 and 1080÷120=9, giving you 16:9. Our calculator does this automatically.

1920x1080 (Full HD or 1080p) has an aspect ratio of 16:9. This is the standard widescreen format used for HD video, most computer monitors, and TVs.

Instagram supports multiple aspect ratios: 1:1 (1080x1080) for square posts, 4:5 (1080x1350) for portrait feed posts, and 9:16 (1080x1920) for Stories and Reels. Square posts get equal visibility on all devices.

4K UHD (3840x2160) has a 16:9 aspect ratio, the same as 1080p. The '4K' refers to the approximate horizontal pixel count (3840 ≈ 4000), not the aspect ratio. Cinema 4K (4096x2160) has a slightly wider 1.9:1 ratio.