On old loans, the period remaining equals the original term less the number of monthly payments you have made, provided you have not made any prepayments. If you have made any extra payments, you can find the period remaining by clicking here and entering your current balance, rate, and monthly payment. Make sure the payment is principal and interest only. If you have been making BW payments, assume the loan is new and enter the original term. If you have been systematically making extra payments, enter these as well. If you have been making extra payments but not systematically, you can't use this calculator.This item is optional. If you want to know your interest payments for the remainder of the first year, indicate the number of biweekly payments you will be making in the first year. The program will default to a full year (26 payments).