Aspect Ratio Calculator
Solve width, height and aspect ratio.
Resolution
1920 × 1080
Simplified ratio
16 : 9
About the Aspect Ratio Calculator
Lock an aspect ratio and solve for the missing width or height — handy for video, images and responsive design. Keep 16:9, 4:3 or any custom ratio without the guesswork.
How to use it
- 1Enter your aspect ratio (e.g. 16:9) or a known dimension.
- 2Type the width or height you have.
- 3Read the matching dimension that preserves the ratio.
Resize without distortion
Whenever you resize an image or video, the width and height have to change in proportion, or the result looks squashed or stretched. Working that out by hand means dividing and multiplying by fractions, which is where mistakes creep in. Lock the ratio you need — 16:9 for widescreen video, 4:3 for classic displays, 1:1 for square social posts, or any custom ratio — enter the one dimension you know, and read the exact matching value. It's the quick way to fit media into a layout, a thumbnail slot or an export preset without guesswork.
Common uses
- Finding the right height for a given width at 16:9 for a video.
- Sizing an image to fit a layout slot without distorting it.
- Working out export dimensions for a specific aspect ratio.
Frequently asked questions
- What aspect ratio should I use for video?
- 16:9 is standard for most screens and platforms; 9:16 is used for vertical/mobile video.
- How do I keep an image from looking stretched?
- Always scale width and height by the same ratio. Enter your ratio and one known dimension here and the tool gives you the matching one, so the proportions stay intact.