This calculator will estimate the mortgage balance owed at the end of the initial payment term when the loan payment has been calculated on a longer term. Balloon Payment Loan Calculator - With this balloon payment calculator you can get the monthly and balloon payment or just the balloon payment itself.A balloon loan is usually rather short, with a term of three to five years, but the payment is based on a term of up to 15 years. This tool figures a loan's monthly and balloon payments, based on the amount borrowed, the loan term and the annual interest rate. Whether you are trying to calculate a monthly payment or figure out a savings goal, these calculators can help you quickly find the information you need. Use the balloon payment calculator to estimate the monthly payment and the final lump sum of a given balloon loan construction. Balloon Loan Payment Calculator. A straight note is a written document that outlines the terms of a loan agreement between a borrower and a lender. When they need to come up with the balloon payment, the borrower could have trouble refinancing. It's impossible to predict the future.