Loans & savings
Compound Interest Calculator
Compound interest means you earn interest on the interest already added. Set the starting amount, the rate and how often it compounds, and add a monthly deposit if you plan to keep saving.
Your result will appear here.
How it's calculated
Without deposits, the balance after t years is the formula below, where r is the yearly rate and n is how many times a year interest is added.
With monthly deposits, each deposit compounds from the month it goes in. The calculator works month by month so it handles any mix of compounding and deposits.
A = P × (1 + r/n)^(n × t)
How to do it in Excel
=FV(5%/12, 10*12, -200, -10000)- Balance after 10 years with monthly compounding and 200 a month.
=10000*(1+5%/12)^(12*10)- The same starting amount with no deposits.