When we take out an installment loan, the amount of the payment depends on three things: the amount of money we borrow (sometimes called the principal), the interest rate (or APR), and the term of the loan. Calculate the monthly payment formula in real time. Here, t is the term in months and r = APR/12 is the monthly interest rate as a ;· An installment loan is one that you pay off over time, usually making the same payment each month for a fixed number of months. Many loans operate this way, including many mortgages that you use to buy houses and real estate and many auto loans that you use to buy Payment = Loan Balance x (annual interest rate/12) In this case, your monthly interest-only payment for the loan above would be $ Knowing these calculations can also help you decide which kind of loan to look for based on the monthly payment ;· 12/07/2021 · Formula to calculate monthly payment Remaining principal balance = initial outstanding balance – principal balance paid periodically Interest paid this month = Remaining balance current applied interest rate number of days to calculate interest30/07/2021 · Interest-Only Loan Payment Formula Calculating payments for an interest-only loan is easier. Multiply the amount you borrow (a) by the annual interest rate (r), then divide by the number of payments per year (n). Or, multiply the amount you borrow (a) by the monthly interest rate, which is the annual interest rate (r) divided by 12: 4 14/03/2011 · This video shows how to calculator the monthly payment for a fixed payment installment ;· Similar to the above example, you’ll enter this data into the PMT function to calculate your monthly payment. Since this loan is paid in monthly installments, the interest rate will need to be divided by 12 and the length of the loan will be multiplied by 12: The formula now reads: