Doubling your money at 1%
Rate: 1%
~72 yr
See the page
Frequently Asked Questions
What do these pages cover?
For every rate from 1% to 20%, a dedicated page shows how long your money takes to double — as a quick Rule of 72 estimate and as the exact value, with a growth curve, live calculator, and accuracy comparison. All figures are illustrative only and not investment advice.
How does the Rule of 72 work?
Divide 72 by the rate as a percent to get a rough number of years to double: 72 ÷ 8 = 9 years at 8%. For tripling use 114, and for quadrupling use 144.
How accurate is the estimate?
Surprisingly accurate. Near 8% the rule is almost exact; at very low or very high rates it drifts a little. Each detail page compares the estimate directly against the exact logarithmic value.
How is the exact value calculated?
With the logarithmic formula ln(2) ÷ ln(1 + r), where r is the rate as a decimal. We use annual compounding — the standard convention for doubling times.
Is this investment advice?
No. These pages explain the math of doubling time at fixed rates. They are not investment, tax, or legal advice. Real returns vary and are never guaranteed.