Aspect Ratio Calculator
Calculate the missing side
Ratio from resolution
Change width or height – the other side is calculated to match the ratio.
Calculate aspect ratios easily
Whether 16:9, 4:3 or 21:9 – the calculator finds the missing edge length for a given aspect ratio. Conversely, it reduces a resolution (e.g. 2560×1440) to its ratio.
- Missing side: Enter a ratio and one edge length – the other is calculated.
- Ratio from resolution: Reduces width and height to the smallest integer ratio (via the greatest common divisor).
- Use: Videos, images, displays and responsive layouts.