Compound Interest Calculator
This compound interest calculator can be used to compare interests of different compound periods. By definition, the commonly used Annual Percentage Rate (APR) is the interest rate compounded annually. Please use the interest calculator if you want to calculate the interest of an investment or saving.
![]()
Compound Interest Formula
Simplified calculation
At = A0(1+r)t
where:
A0 : principal amount (initial investment)
At : amount after time t
r : annual interest rate
t : number of years
Multi-period per year compound
At = A0(1+r/n)nt
where:
A0 : principal amount (initial investment)
At : amount after time t
n : number of times the interest is compounded per year
r : annual nominal interest rate compound every 1/n year
t : number of years
Continuous compounding
At = A0ert
where:
A0 : principal amount (initial investment)
At : amount after time t
r : annual interest rate compound continuously
t : number of years