Aspect Ratio Calculator

Free Online Aspect Ratio Calculator - 16:9, 4:3, 21:9

Calculate aspect ratio from width and height, or calculate dimensions from a ratio and one side. Includes common resolution references.

📐 What is Aspect Ratio?

Aspect ratio is the proportional relationship between width and height. 16:9 is the most common widescreen ratio, while 4:3 is the classic TV ratio. It is essential in video production, design, and photography.

👁️ Ratio Comparison

16:9
4:3
1:1
21:9
9:16
3:2

📺 Common Resolutions

NameResolutionRatio
HD (720p)1280 x 72016:9
Full HD (1080p)1920 x 108016:9
QHD (1440p)2560 x 144016:9
4K UHD3840 x 216016:9
8K UHD7680 x 432016:9
XGA1024 x 7684:3
Instagram Square1080 x 10801:1
Instagram Story1080 x 19209:16
Ultrawide QHD3440 x 144021:9
Super Ultrawide5120 x 144032:9

📖 How to Use

  1. Calculate Ratio: Enter width and height to compute the aspect ratio
  2. Calculate Dimension: Enter a ratio and one dimension to find the other
  3. Click preset buttons to quickly select common ratios

💡 Aspect Ratio Tips

  • YouTube default: 16:9
  • Instagram feed: 1:1 or 4:5
  • Instagram Story/Reels: 9:16
  • Cinema screen: 21:9 or 2.35:1
  • Super ultrawide monitor: 32:9