Existing Loan Analysis Calculator View Calculator Are you paying on a loan and wondering how long you've been paying or how much longer you'll be paying? Just enter your loan balance, interest rate, the original length of the loan, and the current monthly payment and this calculator will show you how long you've been paying and the remaining time to payoff, as well as how much interest and the total paid so far and how much interest and the total remaining to be paid. Learn more about putting this calculator or other calculators on your website.