Calculate the aspect ratio of any image from width and height. Scale dimensions proportionally for social media, video, and web. Free online image aspect ratio calculator.
Calculate the exact aspect ratio of any image from its pixel dimensions and scale to new sizes while maintaining the correct proportional ratio. Enter width and height to get the ratio (e.g., 16:9, 4:3, 1:1), then calculate scaled dimensions for any target size.
Aspect ratio = Width : Height, simplified by GCD. Example: 1920x1080 pixels — GCD(1920,1080) = 120 — so 1920/120 : 1080/120 = 16:9.
Divide the width and height by their greatest common divisor (GCD). For 1920x1080: GCD=120, so 16:9. Enter any dimensions in this calculator for an instant result.
Any size where width/height = 1.777: 1920x1080, 1280x720, 2560x1440, 3840x2160, 640x360, 1366x768.
Square feed: 1:1 (1080x1080), Portrait feed: 4:5 (1080x1350), Stories/Reels: 9:16 (1080x1920), Landscape: 1.91:1 (1080x566).