Car Loan Calculator
Enter your price, down payment, rate, and term to see your monthly payment and the true total interest cost of your auto loan.
How the car loan calculator works
This calculator uses the standard amortizing-loan formula that lenders apply to auto financing. It takes the vehicle price, adds estimated sales tax on the taxable amount (price minus any trade-in), subtracts your down payment and trade-in value to find the amount financed, then spreads that balance plus interest evenly across your loan term.
The monthly payment is calculated as P = A · r / (1 − (1 + r)−n), where A is the amount financed, r is the monthly interest rate (APR ÷ 12), and n is the number of months. Because interest is charged on the declining balance, the longer your term, the more total interest you pay even though the monthly figure shrinks.
Reading your results
Watch the total interest figure, not just the monthly payment. Stretching a loan from 48 to 72 months can cut the monthly cost by a third while adding hundreds or thousands of dollars in interest. Many financial educators suggest keeping auto loans to 48–60 months and total car costs under 15–20% of take-home pay.
Frequently asked questions
Does this include sales tax?
Yes. The calculator adds estimated sales tax to the taxable amount (price minus trade-in) before financing. Tax rules vary by state, so treat it as an estimate.
Is APR the same as interest rate?
For a simple auto loan they're nearly identical. APR can also fold in certain fees, so your lender's APR may be slightly higher than the base rate.
What term should I choose?
Shorter terms cost less overall. Many experts recommend 48–60 months to balance an affordable payment against total interest paid.