## How the Rule of 72 Calculator can help you

Rule of 72 Calculator will help you estimate the number of years needed to double your money at a given interest rate.

** Rule of 72 Calculator also will help you estimate the annual interest rate needed to double an investment in a specified number of years.*

## How to use the Rule of 72 Calculator

1. Select the interest rate or the number of years first;

2. Click on the “Calculate” button to get the results for “Rule of 72 Estimate” and “Exact Answer”.

## Rule of 72 Calculator Formula

**R x T = 72**

T = Number of Periods;

R = Interest Rate as a percentage;