Investment & Returns100% Client-SideInstant Calculation

Rule of 72 Calculator

LIVE COMPUTATION
Annual Interest / Return Rate (%)8%
Time to Double Your Capital (2x)
9 Years
(108 Months)
At a 8% compound return, a $10,000 investment becomes $20,000 in 9 years, and $40,000 in 18.0 years!

How to Use Rule of 72 Calculator

01

Enter your expected annual rate of return.

02

Immediately view the approximate years and months required for your capital to double 2x.

Banking-Grade Privacy Guarantee

Rule of 72 Calculator runs 100% client-side in your web browser. None of your financial figures, bank accounts, income details, loan amounts, or personal tax data are transmitted to any server or saved in cookies. Calculations happen entirely on your local device.

Frequently Asked Questions

How accurate is the Rule of 72?

The Rule of 72 provides remarkably accurate approximations for interest rates between 6% and 10%. For example, at 8%, money doubles in ~9 years (72 / 8 = 9).

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