Compound Interest Calculator
See how a starting amount grows with compound interest, optional monthly contributions, and a simple-interest comparison.
Estimate the regular contribution that reaches a savings target from what you have already saved and a rate you choose.
A savings goal calculator estimates the regular amount to set aside so current savings can reach a target. The rate you enter is an assumption, not a promised return.
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Work backward from a savings target. Enter what you have now, a rate, and how long you have. The page estimates the contribution for each period.
With nothing saved and a 0% rate, the monthly contribution is 10,000 divided by 24.
If current savings are already at or above the target, the page asks for a higher goal or a lower starting amount. It does not show a contribution of 0 as a new plan.
With a 0% rate, the contribution is the gap divided by the number of periods. With a rate, current savings grow by the periodic rate, and each contribution is added at the end of the period. The payment is the amount that makes that future balance equal the target. Sample rates are assumptions, not forecasts.
The rate is an assumption you type. This page does not predict investment returns, taxes, or fees. A target you have already reached is rejected.
See the disclaimer for what these tools do not cover.
See how a starting amount grows with compound interest, optional monthly contributions, and a simple-interest comparison.
Find percentages, increases, decreases and what percent one number is of another.
Estimate how long several debts take to pay off, and the interest, under a highest-interest or smallest-balance plan.
Estimate the monthly payment, interest, and payoff schedule for a fixed-rate installment loan, including a personal loan.
Compare an original number with a new one and see the percent change. From 80 to 100 is a 25% rise; 100 back to 80 is a 20% drop. An original of 0 is rejected.
Take a percent off a price and see the amount saved and what you pay. Type plain numbers. A currency symbol is invalid, and a discount above 100% is rejected.
Guide
Compound interest adds growth onto a balance over time. See the monthly method this calculator uses, including an optional contribution.
Read guideGuide
At 0% interest, divide the gap between the target and what you have saved by the number of deposits.
Read guideAn estimate of the contribution that reaches a target from the rate you enter. The rate is an assumption, not a promised return.
Use 0 if you do not want to assume interest.