Aspect Ratio Calculator
Enter the ratio you need to hold — 16:9, 4:3, 1:1, or anything custom — plus the dimension you already know.
Notes
- Exact results are often fractional. 1000px wide at 16:9 is 562.5px tall, so the rounded row gives 563.
- Rounding one side changes the ratio very slightly, which matters for tiling and print but not for web images.
Common questions
- What aspect ratio should I use?
- 16:9 for video and most screens, 1:1 for profile images and many social posts, 4:5 for portrait social feeds, and 3:2 or 4:3 for photographs.
- Why does my image look stretched?
- Because the width and height were changed by different factors. Set one dimension, calculate the other here, and the proportions hold.