Android app

Proportion Calculator

Enter three values in A : B = C : D, leave one field blank, and calculate the missing value quickly.

Japanese app name: かんたん比例計算

Proportion Calculator
A : B = C : D
50
:
100
=
60
:
120
Result 120

History

50 : 100 = 60 : 120
2 : 5 = 8 : 20

Main features

Proportion Calculator is designed for quick ratio and proportion calculations without unnecessary steps.

Calculate one missing value

Enter any three values in A : B = C : D and leave the value you want to calculate blank.

Clear result display

The calculated value is shown clearly, and the answer field is visually highlighted.

Copy the result

Copy the calculated value and use it in another app, document, or message.

Calculation history

Recent calculations are displayed in the app so you can review previous results.

Useful for

  • Calculating ratios and proportions
  • Finding a missing value in A : B = C : D
  • Adjusting values while keeping the same ratio
  • Work, study, and everyday calculations
  • Quick calculations without complex functions

Privacy

The app is designed to work simply without login, cloud storage, or network communication.

No login

The app does not require users to create an account or sign in.

No cloud storage

Entered values and calculation history are used only inside the app.

No network communication

The app does not need an internet connection for its calculation functions.

No advertising at launch

The initial release is planned without advertising features.

For details, please read the Privacy Policy.