Calculates how long it would take money to double (doubling time) using the rule of 72 interest approximation as well as showing the mathematical proof of the Rule of 72.

This calculator has 1 input.

This calculator has 1 input.

- Doubling Money Time (t) = 0.72/i
- (1 + i)
^{t}= 2

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- approximation
- anything that is intentionally similar but not exactly equal to something else.
- compound interest
- the interest you earn on principal and interest

A = (1 + r/n)^{nt} - interest rate
- the proportion of a loan that is charged as interest to the borrower or proportion of principal credit given to a depositor
- logarithm
- the exponent or power to which a base must be raised to yield a given number
- rule of 72
- a simplified formula that calculates how long it will take for an investment to double in value, based on its rate of return.

t ~ 72/i - yield
- How much an investment returns in terms of interest rate

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- Rule of 72 at 5%
- Rule of 72 at 6%
- Rule of 72 at 7%
- Rule of 72 at 8%
- Rule of 72 at 9%
- Rule of 72 at 10%
- Rule of 72 at 11%
- Rule of 72 at 12%
- Rule of 72 at 13%
- Rule of 72 at 14%
- Rule of 72 at 15%
- Rule of 72 at 16%
- Rule of 72 at 17%
- Rule of 72 at 18%
- Rule of 72 at 19%
- Rule of 72 at 20%
- Rule of 72 at 21%
- Rule of 72 at 22%
- Rule of 72 at 23%
- Rule of 72 at 24%
- Rule of 72 at 25%
- Rule of 72 at 26%
- Rule of 72 at 27%
- Rule of 72 at 28%
- Rule of 72 at 29%
- Rule of 72 at 30%