Rule of 72 Calculator
Divide 72 by the annual return rate to get the approximate years needed to double your money — or enter years to find the required rate.
100% client-side · no upload
Rate → Years
Years to Double
10.3
Years → Rate
Required Rate (%)
7.2%
How to use the Rule of 72 calculator
- Enter an annual return rate in the left panel to see how many years it takes to double your money.
- Or enter a target number of years in the right panel to see what rate is required.
- The Rule of 72 is an approximation — most accurate between 6% and 10% annual rates.
Common use cases
- Stock market: At a historical 7% average return, investments double roughly every 10.3 years.
- Inflation: At 3% inflation, your purchasing power halves in 24 years.
- Savings accounts: A 1% savings account doubles in 72 years — a sobering fact.
Related tools: Compound Interest Calculator · Inflation Impact Calculator · Investment Return Calculator · All Finance Tools
Preguntas frecuentes
- Is this Rule of 72 calculator free?
- Yes, completely free with no signup required. All calculations run in your browser.
- Does my data leave my device?
- No. The calculator runs entirely in your browser with no data sent to any server.
- Does it work on mobile?
- Yes. The tool is mobile-first and works on iPhone Safari and Android Chrome.