Compound Interest Calculator

    Discover how your investments can grow over time with the power of compound interest

    Step 1: Investment Details

    $

    Amount of money that you have available to invest initially.

    $

    Amount that you plan to add to the principal every month, or a negative number for withdrawals.

    years

    Length of time, in years, that you plan to save.

    %

    Your estimated annual interest rate.

    Step 2: Compounding Options

    Times per year that interest will be compounded.

    When contributions are added to your investment.

    Results

    Your investment growth projection

    Final Balance

    $0

    Total Contributions

    $0

    Interest Earned

    $0

    Growth Visualization

    See how your investment grows over time

    Investment Breakdown

    ContributionsInterest
    0.0%0.0%
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    Formula to Use

    Mathematical formulas for compound interest calculation

    Future Value of Initial Investment:

    FVinitial=P×(1+rn)n×tFV_{initial} = P \times \left(1 + \frac{r}{n}\right)^{n \times t}

    Future Value of Contributions:

    FVcontributions=PMT×(1+rn)n×t−1rnFV_{contributions} = PMT \times \frac{\left(1 + \frac{r}{n}\right)^{n \times t} - 1}{\frac{r}{n}}

    Total Future Value:

    FV=FVinitial+FVcontributionsFV = FV_{initial} + FV_{contributions}

    Total Contributions:

    Total contribution=P+(PMT×n×t)\text{Total contribution} = P + (PMT \times n \times t)

    Interest Earned:

    Interest earned=FV−Total contribution\text{Interest earned} = FV - \text{Total contribution}
    FV

    Future Value

    Total final amount

    P

    Principal

    Initial investment

    PMT

    Payment

    Monthly contribution

    r

    Interest Rate

    Annual rate (decimal)

    n

    Compounding

    Times per year

    t

    Time Period

    Years invested

    Compounding Frequency Examples

    1

    Annually

    Once/year

    2

    Semi-annual

    Every 6mo

    4

    Quarterly

    Every 3mo

    12

    Monthly

    Every mo

    365

    Daily

    Every day

    Compound interest creates exponential growth by calculating interest on both your initial principal and accumulated interest. The more frequently interest compounds (higher n), the faster your money grows, as you earn interest on interest more rapidly.