How this calculator works
This calculator estimates finance charges, compares cash price with total payments, and approximates the APR from payment terms. Enter the cash price, down payment, number of payments, and payment amount to see the finance charge and implied annual percentage rate. Use it when comparing installment purchases, evaluating financing offers, or understanding the true cost of credit. The key inputs are cash price, down payment, number of payments, and payment amount. The output is the finance charge and estimated APR. Real-world applications include installment buying, loan comparison, credit cost analysis, and retail financing decisions. The calculator subtracts down payment from cash price, compares total payments with the cash price, and estimates APR using an iterative payment-rate method. It is an estimate based on inputs provided. Fees, payment timing, and contract terms can change the disclosed APR.