Ratio scaling calculator

Keep a ratio constant while changing one of its quantities.

Numbers Stateless

Use a decimal point for fractional values.

Quick guide

Try an example

You enter

First amount
2
Second amount
3
New first amount
10

You get

15
How it works & limits

Enter a positive first and second amount, then the new first amount. The result is the matching second amount.

Related tool

Aspect ratio calculator