Aspect Ratio Calculator
Get the aspect ratio (like 16:9) from a width and height, and compute new sizes that keep the ratio—handy for video and image resizing. Everything runs in your browser.
Enter width and height
FAQ
How is the ratio calculated?
Width and height are divided by their greatest common divisor. Example: 1920×1080 → 16:9.
How do I get a new size?
Enter a new width and the matching height is computed automatically, keeping the original ratio.
Is my input sent to a server?
No. All calculations happen entirely in your browser.
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