A simple mental math shortcut to estimate how long it takes your money to double — or what rate you need to hit a doubling target.
Your money doubles in
—
Doubles 3× in
—
Doubles 5× in
—
7%
$10,000
Doubling time at common rates
Rate
Doubles every
10× your money in
Required annual rate
—
At this rate, $10k becomes
—
10 yrs
How it works: Just divide 72 by the number of years you want to double your money in — the result is the annual return you'd need to make that happen.