proportion solver

Ratio Calculator

Simplify A:B values, scale equivalent ratios, and solve the missing side of a proportion from the same focused workspace.

sample loaded

Ratio setup

The A and B inputs stay editable for every mode.

Ratio calculation mode
Scale an equivalent ratio

Input proportion

Lock either side, then calculate the matching side at the same proportion.

A:B
A2.5
B7.5

Known side

Choose the side to lock while scaling.

B = 30 -> A calculated

Scenarios

4 presets

Current setup: 2.5:7.5, B=30

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