Aspect Ratio Calculator

Find the reduced ratio of any dimensions, or scale one dimension while keeping the ratio fixed

ratio = W/GCD : H/GCD
Ratio
16:9
Decimal
1.7778
16:919201080

About this calculator

Calculate and scale aspect ratios for images, videos, and screens. Find the simplified ratio from dimensions, or scale one dimension while preserving the aspect ratio. Useful for responsive design and video editing.

Common examples

  • 1920×1080 = 16:9 (Full HD)
  • 3840×2160 = 16:9 (4K UHD)
  • 1080×1080 = 1:1 (square)
  • 1080×1350 = 4:5 (portrait)
  • 2560×1440 = 16:9 (QHD)