Interest Calculator
Periodic Deposits

This calculator will show you how much interest you will earn over a given period of time; at any given interest rate; based on an initial investment plus a fixed monthly addition. The calculator compounds monthly and assumes deposits are made at the beginning of each month.

Furthermore, by using a negative deposit amount, it is possible to see the results of withdrawing from an investment (assuming the investment is tax-free upon withdrawal, such as a Roth IRA) - The calculator assumes withdrawals are made at the end of each month.