Rule of 72 Calculator
How fast does your money double?
Rule of 72 Calculator
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The classic rule of thumb: divide 72 by your expected annual return (%) to estimate how many years it takes for your investment to double.
Why Use Our Rule of 72 Calculator
The Rule of 72 is one of the simplest yet most powerful shortcuts in investing.
It lets you quickly estimate how long it will take for your money to double through compound growth — no complex spreadsheets needed.
Just divide 72 by your expected annual rate of return (in percent), and you get a close approximation of the years required.
For example:
At 8% annual return → ~9 years to double
At 6% → ~12 years
At 12% → ~6 years
How to Use Our Rule of 72 Calculator
Enter your expected annual return percentage in the field below and hit “Calculate”.
You’ll instantly see:
The estimated doubling time.
Context on whether that’s fast (higher risk/growth) or slower (defensive/value approach).
This tool uses the classic Rule of 72 formula and includes small notes on when the approximation is most accurate (typically best between 4–15% returns).
Why the Rule of 72 Matters for Long-Term Investors
In value investing and long-term wealth building, understanding compound growth is essential. The Rule of 72 helps answer key questions like:
How many years until my portfolio doubles?
What return rate do I need to hit my financial goals?
Is my current strategy aggressive enough — or too risky?
While it’s not exact (ignores fees, taxes, volatility, and varying returns), it’s remarkably close for quick mental math and planning. Perfect for beginners and experienced investors alike who want fast insights without overcomplicating things.
Try it now — plug in different scenarios and see the power of compounding in action.