Free Online Aspect Ratio Calculator
Aspect ratio describes the relationship between an image's width and height — common examples include 16:9 for widescreen video, 4:3 for older displays, and 1:1 for square social media posts. LovePDFImg's Aspect Ratio Calculator works out the simplified ratio for any pair of dimensions, and can also calculate a proportional width or height when you need to resize an image without distorting it.
Enter your original width and height (or upload an image to fill these in automatically), and the tool shows the simplified ratio. Then enter a target width or height, and the matching dimension is calculated instantly so your resized image keeps the same proportions. This is especially handy when preparing images for templates, social media, or print that require specific ratios.