Rule of 72 Calculator
Estimate how many years it may take for an investment to double at a fixed annual return.
Enter an annual return to calculate.
Practical Example
Start with values whose approximate result you already know. Run the calculator or converter and compare the output, then adjust one value or unit to explore another scenario.
Factors That Affect the Result
Correct units, accurate inputs, conversion constants, rates, market values and rounding can influence the output. Financial estimates can also vary with changing prices, yields and assumptions.
Frequently Asked Questions
Can I use different units or values?
Yes. Enter the values supported by the tool and recalculate as needed.
Why can an external result differ?
Different rounding, assumptions or reference values may produce small differences.
Should financial results be treated as estimates?
Yes. Market-based values can change over time.