Aspect Ratio Calculator
Calculate and convert aspect ratios instantly. Find the ratio from dimensions, resize while keeping proportions, and use common presets like 16:9, 4:3, and 1:1.
Resize Calculator
Enter a new width or height to calculate the other dimension while keeping the aspect ratio
Common Ratios
About This Tool
- Instantly calculate aspect ratio from any dimensions
- Resize calculator maintains proportions automatically
- Common presets for HD, mobile, photo, and more
- Completely free with no registration required
Frequently Asked Questions
An aspect ratio is the proportional relationship between width and height of an image, video, or screen. It's expressed as two numbers separated by a colon, like 16:9 or 4:3.
16:9 is the standard for HD/4K video and monitors. 4:3 is the classic TV/photo ratio. 1:1 is a square (Instagram posts). 9:16 is for vertical mobile video. 3:2 is common for DSLR photos. 21:9 is for ultrawide monitors.
Aspect ratios ensure images and videos display correctly across different devices and screen sizes. Using the correct ratio prevents stretching, cropping issues, and layout problems in responsive design.
Yes, completely free with no registration. Calculate aspect ratios as many times as you need.