Auto Loan Calculator

How an auto loan payment is calculated

Your monthly payment depends on three things: the amount you finance, your interest rate, and your loan term. The amount financed is the vehicle price plus sales tax and fees, minus your down payment, trade-in and any rebates. That figure is amortized over the term, so early payments are mostly interest and later payments mostly principal — the balance chart above shows the curve.

Calcuris computes the exact payment with the standard amortization formula and lets you see the full schedule, the total interest, and the all-in cost of the car including tax and fees — not just the monthly number.

Average auto loan rates in 2026 by credit score

As of late 2025, the average new-car APR was about 6.37% and the average used-car APR about 11.26% (Experian). Your rate depends heavily on your credit: super-prime borrowers (781–850) average around 4.7% on a new car, prime (661–780) about 6.3%, while subprime borrowers pay 13% or more. Used-car rates run several points higher across every tier.

Pick your credit tier above and the calculator prefills a realistic APR; you can always override it with a quote you've been offered. Even a one- or two-point difference in APR changes your total interest by hundreds or thousands of dollars over a 60- to 72-month loan.

Sales tax on a car — and why your state matters

Most states charge sales tax on a vehicle purchase, and it's usually rolled into the loan. The rate varies widely, and so do the rules: five states — Alaska, Delaware, Montana, New Hampshire and Oregon — charge no state sales tax at all. Select your state above and the calculator fills in the average combined rate and applies the correct treatment.

The bigger subtlety is the trade-in tax credit: in most states you only pay sales tax on the price after subtracting your trade-in, which can save hundreds. But eight states — California, DC, Hawaii, Kentucky, Maryland, Michigan, Montana and Virginia — tax the full price regardless. Calcuris models this per state, which most lender and dealer calculators get wrong.

Trade-in value and negative equity

A trade-in lowers the amount you finance and, in most states, the sales tax you pay. But if you still owe money on the car you're trading in and you owe more than it's worth, that's negative equity — the shortfall gets added to your new loan. Enter both your trade-in value and the amount still owed above, and the calculator rolls the difference into the financed amount so your payment reflects reality.

Rolling negative equity forward is common but expensive: you're paying interest on the old car's balance on top of the new one. The total-cost figure above makes that visible.

How much should your down payment be?

A common guideline is 15–20% down on a new car (less on used), enough to offset the steep first-year depreciation and avoid being underwater on the loan. A larger down payment lowers both your monthly payment and your total interest, and can help you qualify for a better rate. Try different down payments above to see the trade-off instantly.

Loan term: 60 vs 72 vs 84 months

Longer terms mean lower monthly payments but more total interest — and a higher chance of owing more than the car is worth. A 72- or 84-month loan can make an expensive car feel affordable while costing you far more over time and keeping you in debt long after the car has lost value. Sixty months is a common balance; compare terms above and watch the total-interest figure, not just the monthly payment.

Cash back vs low-interest financing

Dealers often offer a choice between a cash rebate and a special low (or 0%) APR. The right pick depends on the numbers: a large rebate can beat a low rate on a shorter loan, while low-APR financing usually wins on longer terms or larger balances. Run it both ways above — enter the rebate as an incentive in one scenario and the special APR in another — and compare the total cost.

How much car can you afford?

A widely used rule of thumb is to keep your car payment under 10% of your monthly take-home pay, and total car costs (payment, insurance, fuel, maintenance) under 20%. Use the reverse mode above: enter a comfortable monthly payment and the calculator works backward to the vehicle price you can afford at your rate and term.