Proportion

Android

Solve any rule of three in seconds.

About

Proportion is a focused calculator for direct and inverse proportion problems — the classic rule of three. Type three values and the fourth appears instantly, with no ads, no sign-up and nothing else in the way. Scaling a recipe, converting units, working out a discount: the answer is always one tap from your clipboard.

Features

Direct proportion

Enter a : b = c : x and the missing value is calculated as you type.

Inverse proportion

Switch to inverse mode for problems where one value grows as the other shrinks.

Copy with one tap

Tap the result to send it straight to your clipboard.

20 languages

Proportion follows your phone's language, from English and Portuguese to Japanese and Arabic.