What does saving $250/month for 15 years grow to?

Saving $250 per month for 15 years at 10% return grows to $103,618. You contribute $45,000 of your own money; the remaining $58,618 is compound interest. The longer the horizon, the more interest dwarfs contributions.
Monthly250
Rate10
Years15
Future Value103,618
Contributed45,000
Interest58,618

How this is calculated

Future value of a monthly annuity = payment × ((1+r)^n − 1) / r, where r = annual rate / 12 and n = months.

Common questions

Is this exact?

The math is exact for the inputs shown. Real-world results vary with fees, taxes, timing, and changing rates.

What return/rate should I assume?

For investments, 7% real (after inflation) is a common conservative planning figure. For loans, use your actual APR.

Can I change the inputs?

Yes — the free calculator at aihowtoinvest.com lets you plug in your exact numbers.

Run your own numbers — free at aihowtoinvest.com →

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