Compound Interest Calculator
See how your starting money and regular contributions could grow over time when interest is compounded.
Your Compound Growth Estimate
This is an estimate for educational purposes. Actual returns may differ because of changing interest rates, fees, taxes, inflation and the actual timing of deposits and interest.
What Is Compound Interest?
Compound interest is interest earned on both your original money and the interest that has already accumulated. Over time, this can allow your balance to grow faster than simple interest.
When you also make regular contributions, each contribution has the opportunity to grow over the remaining period.
How Does a Compound Interest Calculator Work?
This calculator combines your initial amount with your regular monthly contributions and applies the annual interest rate according to the compounding frequency you select.
Monthly contributions are treated as end-of-month contributions. The calculation then estimates the future value of the starting amount and contributions over the selected period.
The Power of Time
Compound growth becomes more noticeable over longer periods because previous interest can remain in the account and participate in future growth.
Compound Growth Regular Contributions Long-Term Saving Future ValueWhy Use a Compound Interest Calculator?
A compound interest calculator can help you estimate how different savings or investment scenarios may develop over time.
You can change the starting amount, monthly contribution, interest rate, time period and compounding frequency to compare different scenarios.
Compound Interest Formula
For a starting amount, the standard compound-growth formula is based on the principal, annual interest rate, number of compounding periods and time.
When regular contributions are included, the future value of those contributions is added to the future value of the original amount. The calculator performs these calculations automatically.
What Can Affect Compound Growth?
Interest Rate
A higher assumed rate can produce a higher projected future value, while a lower rate produces a lower projection.
Time
The length of time your money remains invested or saved can have a significant effect on the amount of compound growth.
Regular Contributions
Adding money consistently can increase the amount of capital that has the opportunity to grow.
Compounding Frequency
Compounding frequency determines how often interest is calculated and added under the assumptions used by the calculator.
Compound Interest Calculator FAQs
What is compound interest?
Compound interest is interest calculated on the original amount plus accumulated interest from previous periods.
Does this calculator include monthly contributions?
Yes. You can enter a regular monthly contribution and the calculator estimates how those contributions may grow over the selected period.
What does compounding frequency mean?
Compounding frequency refers to how often interest is calculated and added under the selected calculation model. This calculator supports monthly, quarterly, semi-annual and annual compounding.
Does a higher interest rate always mean more money?
A higher assumed rate produces a higher mathematical projection when all other inputs remain unchanged. Actual financial products may have different rates, risks, fees and conditions.
Are compound interest calculator results guaranteed?
No. Results are estimates based on the assumptions entered. Actual returns can vary over time.
Does this calculator account for inflation and taxes?
No. The displayed result is a nominal estimate and does not automatically account for inflation, taxes or fees.