Aspect Ratio Calculator

Calculate proportional dimensions and simplify aspect ratios for images and video.

Formula

newHeight = newWidth × (originalHeight / originalWidth)

Tips

  • Common ratios: 16:9 widescreen video, 4:3 legacy displays, 1:1 square social posts, 9:16 vertical/stories, 3:2 most DSLR sensors.
  • Scaling to a non-integer height causes half-pixel rendering. Round to an even number for video encoding.

Frequently asked questions

Why does my video need even dimensions?

Most codecs (H.264, H.265) subsample chroma in 2×2 blocks, so both width and height must be divisible by 2 — some encoders require multiples of 4 or 16.