Compound Interest Calculator

Calculate compound interest with flexible compounding periods. See how your money grows over time with principal, rate, and period inputs.

Enter values to calculate
Compound interest is calculated using A = P(1 + r/n)^(nt), where P is principal, r is annual rate, n is compounding frequency, and t is time in years.

How to Use This Tool

  1. 1

    Enter your principal amount

    Type the initial investment or deposit amount. This is the starting sum on which interest will be calculated.

  2. 2

    Set the annual interest rate

    Enter the yearly interest rate as a percentage. For example, enter 5 for a 5% annual rate.

  3. 3

    Choose compounding frequency

    Select how often interest is compounded: monthly (12x/year), quarterly (4x/year), or yearly (1x/year). More frequent compounding yields higher returns.

  4. 4

    View your results

    The calculator instantly shows the final amount, total interest earned, and growth percentage. Click any result to copy it.

Frequently Asked Questions

What is compound interest?
Compound interest is interest calculated on both the initial principal and the accumulated interest from previous periods. Unlike simple interest, it allows your money to grow exponentially over time.
How does compounding frequency affect returns?
More frequent compounding (e.g., monthly vs. yearly) results in slightly higher returns because interest is added to the principal more often, allowing each new interest calculation to include previously earned interest.
What is the compound interest formula?
The formula is A = P(1 + r/n)^(nt), where A is the final amount, P is the principal, r is the annual interest rate (decimal), n is the number of compounding periods per year, and t is the number of years.
Can I use this for loan calculations?
This calculator shows how an investment grows with compound interest. For loan repayment schedules with monthly payments, use our Loan/Mortgage Calculator which accounts for regular payment deductions.