Aspect Ratio Calculator Step By Step
Aspect Ratio Calculator runs in three steps: enter your original size, read the simplified ratio, then scale to a new size. This page walks through what each step expects.
Step 1 - enter the original width and height
Go to Aspect Ratio Calculator and type the original width and height in the two top fields (for example 1920 and 1080). Nothing needs to be installed or signed in.
Step 2 - read the simplified ratio
The tool reduces the pair to its lowest whole-number terms right away (1920x1080 becomes 16:9) and shows the decimal value underneath.
Step 3 - scale to a new width or height
Type a target width or height in the lower two fields and the other side fills in automatically, keeping the same ratio. Or tap one of the common-ratio buttons (16:9, 4:3, 1:1, and more) to jump straight to that ratio.
The calculation runs locally in the browser - no upload and no account.
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