Proportion Solver

Solve proportions and cross multiplication

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Solve Proportion: A/B = C/D

=

Leave one field empty to solve for it

D =

8

3/4 = 6/?

Cross Multiplication Method

A × D = B × C

3 × 8 = 4 × 6

Direct Proportion Calculator

If X increases, Y increases proportionally

25

Inverse Proportion Calculator

If X increases, Y decreases proportionally

6

Percentage Proportion

X is what percent of Y? Or X% of Y is what?

%

25 is 25.00% of 100

Common Proportions

Golden Ratio:1 : 1.618Silver Ratio:1 : 2.414Rule of Thirds:1 : 216:9 (Widescreen):16 : 94:3 (Standard):4 : 31:1 (Square):1 : 1

About Proportion Solver

Solve proportions and cross multiplication

Use this free online math tools tool to work faster without installing extra software. The interface is built for quick input, clear output, and straightforward results on desktop and mobile devices.

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This tool runs in your browser whenever possible, which keeps your inputs private and reduces unnecessary round-trips to the server.