Period loan interest calculator

Interest is charged on outstanding principal for the matching interest period, not on the installment alone.

I = P_{\text{open}} \times i

Calculator

Enter the values you know and leave one box empty. Calculate finds the empty one, the result or any input.

Given

I = 180{,}000 \times 0.055 = 9{,}900

Symbol	Meaning	Unit
$I$	interest for one period	$
$P_{\text{open}}$	opening outstanding principal	$
$i$	period interest fraction	fraction

Results are estimates for study and screening. Check the inputs, units and assumptions before you use them for design, billing or contract decisions.