calculate aspect ratios and resize dimensions while keeping proportions. presets for 16:9, 4:3, 1:1, and more.
Aspect Ratio Calculator helps you resize dimensions while maintaining proportions. Enter a width and height, and the calculator shows the aspect ratio. Lock the ratio and change one dimension — the other adjusts automatically.
Choose from common presets like 16:9 (widescreen video), 4:3 (presentations), 1:1 (square), 9:16 (vertical video), 3:2 (photography), and 21:9 (ultrawide). A visual preview shows the proportions.
Essential for resizing images, videos, and design elements without distortion.
Enter dimensions
Type a width and height to calculate the aspect ratio, or choose a preset like 16:9 or 4:3.
Lock the ratio
With the ratio locked, changing one dimension automatically adjusts the other to maintain proportions.
See the preview
A visual rectangle shows the proportions of your current dimensions.
Copy the values
Use the calculated dimensions for your image editing, video export, or design project.
Video production
Calculate dimensions for different video aspect ratios (16:9, 4:3, 9:16 vertical).
Responsive web design
Calculate proportional dimensions for responsive images and containers.
Image resizing
Find the right dimensions to resize an image without stretching or distortion.
Print design
Calculate proportional dimensions for print materials at different sizes.
Display fitting
Figure out how content at one aspect ratio fits on screens of different ratios.
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