Start at 16

The same monthly savings started at 16 versus later, and the gap compounding opens between them.

$326,817

is the cost of waiting from age 16 to 30. Both savers put in $100 a month until 65. The early saver contributes only $16,800 more of their own money.

Start at 16Start at 30

Start at 16

$506,922

$58,800 put in, $448,122 earned by the money itself.

Start at 30

$180,105

To catch up, this saver would need about $281 a month instead of $100.

›How this is calculated

Each month the balance grows by the monthly rate (yearly rate ÷ 12) and then the new deposit is added: future value = deposit × ((1 + r)^n − 1) ÷ r.

Real investments do not grow smoothly. A 7% average includes years like 2008, when U.S. stocks fell about 37%. Try the simulator to see real paths.

A teen with earned income, even from a summer job, can open a custodial Roth IRA with a parent, where this growth can be tax free in retirement.

For learning only. Kuleana Finance explains how money works. It does not tell anyone what to buy or sell.