Aspect ratio and resolution calculator

Enter a resolution to see its aspect ratio, then enter a new width to get the matching height.

About this tool

The ratio is width divided by height, reduced with the greatest common divisor. Common ratios: 16:9 for video and most screens, 9:16 for vertical video, 1:1 for square posts, 4:3 for older displays and 4:5 for portrait social posts. Many video encoders need even dimensions; round to the nearest even number if needed.