Aspect Ratio Calculator
Simplify a width and height to its aspect ratio, or calculate a missing width or height from a chosen ratio.
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Result
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Calculated locally. Your numbers never leave your browser.
Common questions
Does this work with decimal dimensions, not just whole numbers?
Yes — a decimal like 16.5 × 9 is scaled up based on the precision you actually typed before simplifying, rather than being rounded off first, so the ratio still comes out exact.
Is the calculated missing dimension rounded?
Yes, to 2 decimal places for display — real-world dimensions rarely need more precision than that. The underlying math itself isn't rounded, only what's shown.
What happens with invalid dimensions, like 0 or a negative number?
They're rejected — every dimension, in either mode, must be greater than zero, with a message asking for a valid value rather than a nonsensical ratio.