Effective annual interest rate or annual equivalent rate calculator.
The effective period interest rate is equal to the nominal annual interest rate divided by the number of periods per year n:
Effective Period Rate = Nominal Annual Rate / n
The effective interest rate is equal to 1 plus the nominal interest rate in percent divided by the number of compounding persiods per year n, to the power of n, minus 1.
Effective Rate = (1 + Nominal Rate / n)n - 1