Doubling Time Calculator
Enter a growth rate to find how long it takes for a value to double. Shows both the Rule of 72 approximation (72 / rate) and the exact doubling time using ln(2) / ln(1 + r).
Inputs
Results
Rule of 72 (Approx)
10.29 periods
Exact Doubling Time
10.2448 periods
Approximation Error
0.0409 periods
Tripling Time
16.2376 periods
Quadrupling Time
20.4895 periods
10x Time
34.0324 periods
Frequently Asked Questions
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