Auto Loan Calculator

About the Auto Loan Calculator

An auto loan calculator helps you understand the full cost of financing a vehicle before you sign a deal at the dealership — showing your monthly payment, total interest paid over the loan term, and the complete amortisation schedule for any combination of vehicle price, down payment, trade-in value, loan term, and interest rate. Buying a car is one of the largest financial decisions most households make, yet many buyers focus exclusively on the monthly payment number rather than the total cost — a framing dealers deliberately encourage because it obscures the true expense of long loan terms and high interest rates. Our free auto loan calculator lets you compare different scenarios side by side: 48 vs 72-month terms, different down payment amounts, dealer financing vs. pre-approved bank rates, and new vs. used vehicle financing rates. It works for new cars, used cars, trucks, SUVs, and any personal vehicle purchase, with inputs in US dollars, UK pounds, Canadian dollars, and Australian dollars.

How It Works

Auto loan payment formula: M = P x [r(1+r)^n] / [(1+r)^n - 1], where P is the loan amount (vehicle price minus down payment and trade-in), r is monthly interest rate (APR / 12), and n is the number of monthly payments. Example: $32,000 vehicle, $4,000 down payment, $2,000 trade-in, 7% APR, 60-month term. P = 32,000 - 4,000 - 2,000 = $26,000. r = 0.07/12 = 0.005833. M = 26,000 x [0.005833 x (1.005833)^60] / [(1.005833)^60 - 1] = $514/month. Total paid: $514 x 60 = $30,840. Total interest: $30,840 - $26,000 = $4,840. Extending to 72 months reduces payment to $444/month but increases total interest to $5,968 — paying $1,128 more for the convenience of $70 less per month.

Tips & Best Practices

• ✓Get pre-approved by your bank or credit union before visiting a dealership — walk in with a committed rate and use dealer financing only if they beat it. Dealers earn significant profit from finance markups.
• ✓The 20/4/10 rule: 20% down payment minimum, 4-year maximum loan term, and total vehicle costs (payment + insurance) under 10% of gross monthly income. This prevents vehicles from becoming a wealth-destroying expense.
• ✓New versus used financing rates: new car loans typically carry lower interest rates (5-7% for good credit) than used car loans (7-12%). Offset this with the higher depreciation on new vehicles — a new car loses 15-25% of value in the first year.
• ✓Dealer add-ons inflate the loan: extended warranties, GAP insurance, paint protection, and accessories added to the loan are financed at your full loan rate — a $1,500 extended warranty at 7% over 60 months actually costs approximately $1,780.
• ✓GAP insurance: if you put less than 20% down on a rapidly depreciating vehicle, GAP coverage protects you if the car is totalled and you owe more than its current value. Buy it from your insurance company, not the dealer — dealer GAP is typically 3-5x overpriced.
• ✓A 1% difference in APR on a $25,000 loan over 60 months saves approximately $650 total — worth shopping multiple lenders for a better rate before committing.
• ✓Balloon payments and deferred interest loans: some dealer financing offers unusually low monthly payments that hide a large "balloon" final payment. The auto loan calculator reveals total cost and flags unusual payment structures.
• ✓Electric vehicle tax credits: up to $7,500 federal tax credit for qualifying new EVs effectively reduces the purchase price. Apply this before calculating the loan amount for a more accurate monthly payment projection.

Who Uses This Calculator

Car buyers comparing dealer financing against bank pre-approval before visiting a dealership. Consumers deciding between vehicle price points by seeing how $3,000 more in purchase price translates to monthly payment and total cost. Families determining whether a new versus used vehicle makes more financial sense when total-cost-of-ownership calculations are included. People deciding on loan term length, understanding the payment versus total interest tradeoffs concretely. Financial advisors helping clients make vehicle purchase decisions within overall budgetary constraints. Dealers and finance managers preparing financing scenarios for customer presentations.