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Estimate growth and interest earned from compounding over time.
A quick overview to help you understand what this tool does and how to use it well.
Use this compound interest calculator to estimate how a balance can grow over time based on the starting principal, annual interest rate, compounding frequency, and number of years. This tool is useful for projecting savings growth, investment balances, and other scenarios where interest is added repeatedly over time.
By adjusting the inputs, you can quickly compare how different rates, time periods, and compounding schedules affect your future balance.
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Your result updates after a successful calculation.
Estimated final balance
$16,470.09
Projected total balance after compounding.
Interest earned
$6,470.09
Growth above the original starting amount.
See the formula, calculation method, and reasoning behind the result.
This calculator estimates future value using the standard compound interest formula:
A = P(1 + r / n)^(nt)
Where:
Compound interest works by applying interest not only to the original principal, but also to interest that has already been added in previous periods. Over time, this causes growth to build on itself.
In general:
Estimate the future value of a $10,000 starting balance at 5% annual interest, compounded monthly, over 10 years. This example shows how a starting balance grows when interest is compounded monthly over a long period. Even without additional contributions, compounding increases the total balance because each interest calculation builds on the previous one.
Example results
Common questions about this tool.
No. This version only models growth from the initial principal.
It is how often interest is added to the balance each year, such as 12 for monthly compounding.
Compound interest is interest calculated on both the original principal and the interest already earned over time. This allows the balance to grow faster than simple interest.
Compounding frequency determines how often interest is added to the balance. More frequent compounding can slightly increase the final amount because interest begins earning additional interest sooner.
The most important factors are the starting balance, the interest rate, the compounding frequency, and the amount of time the money remains invested. In many cases, time has the greatest long-term impact.
No. Simple interest is calculated only on the original principal, while compound interest is calculated on the principal plus previously earned interest.
Yes, this calculator can be used for savings accounts, investments, and other balances that grow through compound interest.
Over longer time periods, each round of earned interest has more opportunities to generate additional interest. That compounding effect becomes more noticeable the longer the balance remains invested.