Loan Payoff Calculator
Give a loan your current payment, then add extra: see the new debt-free date and the interest the extra payments rescue, side by side with the do-nothing path.
Your payment is the schedule
A loan has no fixed lifespan — it has a payment, and the lifespan follows. This calculator runs your loan at the payment you make today, then at that payment plus your extra, and lays the two endings side by side: months to debt-free and interest paid on each path.
Each month: interest = balance × rate ÷ 12 · remainder of the payment cuts the balance
Example: $20,000 at 6%. At $400 a month: 58 payments, $3,072.27 of interest. At $500 a month: 45 payments, $2,370.33. The extra $100 a month deletes 13 payments and $701.94 of interest — the exact shape of every payoff decision on this page.
The guarantee hiding in plain sight
Extra principal payments earn a return equal to the loan's rate, with zero risk and zero tax on the 'gain' — there is no market investment that can promise that. The competing uses of the money (emergency savings, matched retirement contributions, costlier debt) are about ordering, not about whether the return is real.
How this is calculated
A month-by-month simulation for both scenarios: each month interest accrues on the opening balance at the nominal rate ÷ 12, then the payment (plus extra, in the second run) is applied, final payment trimmed to the exact remainder. If the base payment fails to cover the first month's interest, the page reports that instead of inventing an ending.
Frequently asked questions
Does paying extra on a loan hurt my credit?
No — it generally helps utilization and payment-history metrics. The loan closing earlier can slightly change account-age averages years later, a trivial effect next to the interest saved.
One big extra payment or monthly extras?
The big payment wins slightly if made today (principal falls sooner); monthly extras win on realism for most budgets. Both beat the contractual schedule by the same mechanism.
Which loan should get my extra money?
Mathematically, the highest rate (the avalanche order). If several debts compete for the extra, the debt-payoff calculator simulates the whole set at once.
Are there prepayment penalties?
On most modern US consumer loans, no — but 'most' is doing work in that sentence. Mortgages and auto loans are generally clean; some online personal and business products are not. Your note's prepayment clause governs.
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CalcPrincipal