Invest in our Loan Payment Calculator Pocket Slider™, an easy way to calculate your loan payments with carrying interest rates and loan term periods! Determine the amount of principal plus interest, also borrowing tips. Along with tips, we help calculate your loan payments based on your interest rate (from 0.9% to 17-1/2%) and the length of the loan (1 to 30 years). Pocket Sliders are a handy slide chart the size of a #10 envelope!