Aspect Ratio Calculator
Calculate missing dimensions or find aspect ratios. Set a known width or height and get the matching dimension instantly.
Simplified ratio: 16:9
What an Aspect Ratio Calculator Does
An aspect ratio expresses the relationship between width and height, such as 16:9 or 4:3. If you know one dimension of an image, video, or responsive element, this calculator finds the matching dimension so the layout keeps the same shape on every screen.
Where This Matters
- Scaling video thumbnails without cropping or letterboxing
- Creating responsive images for 16:9 and 9:16 layouts
- Checking that custom dimensions simplify to a clean ratio
Does this work for CSS?
Yes. The simplified ratio can be used with CSS aspect-ratio or padding-top techniques to keep an element proportional.