Rule of 72
Compare the quick doubling-time rule with exact compound growth.
Your numbers
Rule-of-72 estimate
Educational estimate using your entered assumptions; no live prices, tax rules or guaranteed returns.
Scenario comparison
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Formula
The rule gives t ≈ 72/p, while constant compound growth gives t = ln(2)/ln(1+p/100). p is the positive annual percentage rate and t is years. The rule is an approximation.
Compare the quick doubling-time rule with exact compound growth.
Worked example
- Annual growth rate (%)
- 6
- Rule-of-72 estimate
- 12 years
- Exact annual compounding
- 11.8956610459 years
Scope and limitations
Educational estimate using your entered assumptions; no live prices, tax rules or guaranteed returns.
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Formula version: 7c261970585c · Example checked: