Compound Interest Calculator
See how your savings grow with compound interest and monthly contributions. Choose daily, monthly, quarterly or yearly compounding.
About the Compound Interest Calculator
Compound interest means you earn interest on your interest, so money grows faster the longer you leave it. This compound interest calculator shows the future value of your savings or investments with regular monthly deposits and a yearly growth table.
How to Use the Compound Interest Calculator
- Enter your starting amount and monthly contribution.
- Enter the expected annual interest rate and number of years.
- Choose the compounding frequency and press Calculate.
Formula and How It Works
Future value without deposits: A = P × (1 + r/n)^(n × t). With monthly deposits, each deposit grows from the month it is added. The calculator simulates every month so the result is exact for any compounding frequency.
Frequently Asked Questions
What is the rule of 72?
Divide 72 by the annual interest rate to estimate how many years it takes to double your money. At 8% it takes about 9 years.
Does compounding frequency matter much?
More frequent compounding gives slightly more, but the interest rate and time invested matter far more.
Results are estimates for planning purposes only and are not financial advice. Actual figures from your bank or lender may differ.