Aspect Ratio Calculator 16:9 and Dimensions
Calculate an aspect ratio (16:9…) and derive a missing proportional dimension.
🔒 100% client-side — no data sent
Calculate an aspect ratio and derive proportional dimensions (missing width or height) for videos, images and containers. Enter a ratio like 16:9 and get the exact size. Everything is computed in your browser, with no data sent anywhere.
What is it for?
- ▸ Find the height of a 16:9 video for a given width
- ▸ Resize an image while keeping proportions
- ▸ Simplify a ratio from pixel dimensions
- ▸ Prepare responsive containers with the right ratio
FAQ
How do I find a missing dimension?
Enter the ratio and one dimension: the missing value is derived automatically.
Can I get the ratio from dimensions?
Yes, provide width and height and the simplified ratio is computed.
Which ratios are supported?
Any custom ratio, including 16:9, 4:3, 1:1 and 21:9.