Webtools Number Tools Ratio Calculator

Ratio Calculator

Solve for a missing value in a ratio, or simplify a ratio to lowest terms.

Solve A : B = C : D

Leave one field blank — it will be solved.

: = :

Missing value =

Simplify a ratio

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About the Ratio Calculator

This ratio calculator solves proportions and simplifies ratios. To find a missing value, enter any three of the four numbers in the proportion A:B = C:D and the calculator finds the fourth. To simplify a ratio, enter both values and get the reduced form.

Common uses include scaling recipes up or down, mixing paints or solutions to a specific ratio, resizing images while maintaining aspect ratio, and solving proportion problems in maths. Works with any numerical values, including decimals.