How a car loan payment is calculated
A car loan is an amortising loan, so the monthly payment is fixed and each instalment covers interest plus a portion of the principal. The amount financed is the vehicle price minus your down payment and any trade-in credit, and the lender solves for the payment that clears that balance over the term. This calculator applies the standard formula and surfaces the total interest, which is the figure dealers rarely highlight. Lowering the amount financed — by putting more down or trading in a vehicle — cuts both the monthly payment and the lifetime interest, because you are simply borrowing less money for the same period.
Why the loan term is a trap
Dealers often steer buyers toward 72- or 84-month loans because the longer term produces a smaller, more appealing monthly payment. The catch is total interest: stretching a loan over seven years instead of four can add thousands to the cost of the same car, and it raises the risk of being 'underwater' — owing more than the car is worth — because vehicles depreciate faster than a long loan pays down. Use this calculator to compare terms on total interest, not the monthly figure, and choose the shortest term whose payment your budget can comfortably absorb.
APR, dealer financing and your credit
The interest rate on a car loan depends heavily on your credit score, the lender and whether the deal is a manufacturer promotion. Dealer financing is convenient but not always cheapest; a pre-approval from your bank or credit union gives you a benchmark APR to negotiate against. Always compare offers using APR rather than the monthly payment, since a lower payment can hide a longer term or a higher rate. Enter each quote here to see the true monthly and total-interest difference side by side.
The costs this calculator leaves out
Financing is only part of car ownership. Sales tax, registration, documentation fees and optional add-ons like extended warranties or gap insurance are often rolled into the loan, increasing the amount financed — add them to the price field to model their effect. Beyond the loan sit insurance, fuel, maintenance and depreciation, the largest hidden cost of all. Budget for the total cost of ownership, not just the payment this tool shows. These calculators use standard financial formulas and the figures you enter. Real interest rates, lender fees and tax treatment vary by bank and country, so treat the results as planning estimates and confirm exact numbers with your lender or a qualified adviser before committing.
Frequently asked questions
How is a car loan monthly payment calculated?
The amount financed (price minus down payment and trade-in) is repaid with the standard amortisation formula at your APR over the loan term, producing one fixed monthly payment that includes interest and principal.
How much should I put down on a car?
A larger down payment lowers your monthly payment and total interest and reduces the risk of owing more than the car is worth. Many buyers aim for around 20% on a new car, but any extra helps.
Is a longer car loan term cheaper?
No. A longer term lowers the monthly payment but increases total interest and the chance of going underwater as the car depreciates. Compare offers on total interest, not the instalment.
Does this include tax and fees?
It calculates the loan only. Sales tax, registration and dealer fees are often financed too — add them to the vehicle price to see their effect on your payment.