Debt Payoff Calculator - Payment and Extra Amount

Paying extra principal is the simplest way to shorten a loan without refinancing. The debt payoff calculator first computes the scheduled amortizing payment from balance, annual rate, and term, then adds any extra monthly amount you plan to send. The headline is the cash you need each month; the detail converts that total into an estimated month count so you can see whether $50 extra is worth it. The scheduled piece is the standard formula with r = APR / 1,200 and n = years × 12. A $10,000 balance at 12% for 3 years has a scheduled payment of $332.14. Adding $50 extra makes the monthly total $382.14 and, because every extra dollar goes to principal after interest is covered, the calendar shortens to about 31 months instead of 36. A 0% balance of $5,000 over 2 years is $208.33 a month with no extra. Use the result when you set a payoff date, when a lender allows extra principal without penalty, or when you compare extra payments with a refinance. Extra payments on simple-interest installment loans and on most mortgages reduce principal immediately. Some precomputed consumer loans (Rule of 78s) do not reward early payoff the same way; read the contract. The month estimate uses the closed-form nper formula on the total payment (scheduled plus extra). It assumes the extra amount is paid every month, the rate is fixed, and there are no fees. Skipping a month or cutting the extra resets the path. Biweekly extra payments are not modeled as 26 half-payments; enter the monthly equivalent. Recalculate after a principal reduction, a rate change, or a new extra amount. If the extra field is blank, the displayed payment equals the scheduled payment and the month count should match the term. Confirm with the servicer that extra amounts are applied to principal rather than advanced as future installments. Used that way, the debt payoff calculator turns a term and an extra dollar amount into a payment you can actually budget.