Compound Interest Calculator
See how your savings grow over the years
Your Savings Plan
Showing growth on your initial investment alone.
Enter the APY your bank advertises. That figure already includes the bank's compounding, so growth here matches a real account.
Future Balance
$0
Growth Over Time
Summary
Turn the plan into a habit
A projection is only as good as the follow-through. Do Budget helps you set savings goals, track every contribution, and see your net worth climb month after month.
Start your free trialFrequently asked questions
What is compound interest?
Compound interest is the interest you earn on both your original money and on the interest it has already earned. Over time the growth accelerates, because each period you earn a return on a slightly larger balance. It is often called earning interest on your interest.
How do regular contributions change the result?
Adding a fixed amount every week, month, or quarter means more of your money starts compounding sooner. Small, consistent deposits often grow into more than a single large lump sum, because every contribution has years of compounding ahead of it. This calculator lets you test any contribution amount and frequency.
Does this match how my bank pays interest?
Yes. Banks advertise an APY (annual percentage yield), a figure that already includes their compounding, and they accrue interest so that a year of principal earns exactly that yield. This calculator uses the APY you enter the same way, and every contribution starts earning from the period it lands in, just like a real savings account where deposits earn from the day they post.
What is APY, and where do I find it?
APY is the annual percentage yield, the headline rate banks show on savings accounts and GICs. It is the true yearly growth after the bank compounds your interest, so it is the number to enter here. If your statement only lists a nominal rate, the APY is slightly higher; when in doubt, use the rate the bank markets most prominently.
What interest rate should I use?
Use the APY that matches where your money sits. High-interest savings accounts and GICs commonly range from 2% to 5%, while a diversified stock market portfolio has historically averaged around 7% a year before inflation over the long run. Returns are never guaranteed, so it helps to test a few rates.
Does this account for taxes and inflation?
No. The projection shows nominal growth before any taxes on interest and before inflation reduces buying power. Treat the result as a best-case picture of gross growth, and remember that a dollar in the future buys less than a dollar today.
Estimates only. Uses the APY you enter (the rate banks advertise), with each contribution earning from the period it is made. Figures are before tax and inflation and assume a constant rate. Actual returns will vary.