Auto Loan Calculator
Calculate your monthly car payment, total loan cost, and interest in seconds. Get a clear breakdown of your auto loan.
Buying a home too? Try our Mortgage Calculator.
An auto loan calculator removes the guesswork from financing a vehicle — before you sit down with a dealer or sign with a lender. This auto loan calculator uses the standard amortization formula to estimate your monthly car payment, total loan cost, and total interest paid based on vehicle price, down payment, trade-in value, sales tax, loan term, and APR. Most buyers focus on the monthly payment, but total interest is what determines whether a financing deal actually costs you more or less over time. A longer loan term lowers your monthly payment but almost always increases total interest paid. Running a few scenarios through this auto loan calculator before committing to financing terms takes minutes and can save hundreds to thousands of dollars over the life of the loan. Supports both new and used vehicle financing.
How to Use the Auto Loan Calculator
- Enter the vehicle price — the sticker or agreed purchase price before tax.
- Enter your down payment — the cash you are putting down upfront (enter $0 if none).
- Enter a trade-in value if you have one — this reduces the amount financed (enter $0 if none).
- Enter your local sales tax rate as a percentage (e.g. 8.5 for 8.5%).
- Enter the loan term in months — 36, 48, 60, and 72 months are the most common.
- Enter your APR — the annual percentage rate your lender has quoted.
- Click "Get my payment" to see your full loan breakdown instantly.
Auto Loan Example: $25,000 at 6% APR
A borrower finances $25,000 with no down payment, no trade-in, and no sales tax at 6% APR. Here is how two common loan terms compare:
| Loan Term | Monthly Payment | Total Interest Paid |
|---|---|---|
| 60 Months | $483/mo | $3,980 |
| 72 Months | $414/mo | $4,808 |
Extending from 60 to 72 months saves $69 per month but costs an extra $828 in total interest for the exact same loan. The longer the term, the more you pay — even at the same APR.
When Would You Use This?
Comparing dealership financing against a bank or credit union offer. Dealers routinely quote a monthly payment without showing the total cost. Enter both offers into this auto loan calculator to see which deal costs less over the full loan term — not just which has a lower monthly number. A lower monthly payment from a longer term or higher APR can easily cost $1,000 or more extra in interest.
Deciding how much to put down. A larger down payment reduces the financed amount directly, which cuts both the monthly payment and total interest. On a $25,000 loan at 6% over 60 months, putting $5,000 down lowers the monthly payment from $483 to $387 and saves approximately $780 in interest. Running two scenarios shows the exact dollar value of saving more before buying.
Choosing a loan term. A 72-month loan keeps your monthly payment low but costs more in total interest than a 48- or 60-month term on the same loan. Comparing terms side by side makes the real cost of each option visible, so you can make an informed trade-off between cash flow and total borrowing cost.
Frequently Asked Questions
How do you calculate a car loan payment?
A car loan payment uses the standard amortization formula: M = P × [r(1+r)^n] / [(1+r)^n − 1], where P is the loan principal, r is the monthly interest rate (annual APR divided by 12), and n is the total number of monthly payments. For a $25,000 loan at 6% APR over 60 months, r = 0.005 and n = 60, producing a monthly payment of approximately $483. This auto loan calculator applies that formula after adjusting for down payment, trade-in, and sales tax to give you the financed amount first.
Why do down payment and trade-in value matter?
Every dollar of down payment or trade-in value is a dollar you do not borrow — and therefore do not pay interest on for the entire loan term. On a $25,000 car at 6% APR over 60 months, a $5,000 down payment reduces the financed amount to $20,000, cutting the monthly payment from $483 to $387 and saving approximately $780 in total interest. A trade-in works identically — its value is subtracted from the financed amount before the payment is calculated.
Why does APR matter in an auto loan?
APR is the annual cost of borrowing — it determines how much interest accrues each month on your remaining balance. On a $25,000 auto loan over 60 months, the difference between 6% and 7% APR is approximately $12 more per month and roughly $720 more in total interest. Shopping for a lower APR through a credit union or bank before accepting dealer financing is often the single most effective way to reduce the total cost of an auto loan.
Why does loan term affect total cost?
A longer loan term spreads payments over more months, which lowers each payment but allows interest to accumulate longer on a higher remaining balance. On a $25,000 loan at 6% APR, extending from 60 to 72 months saves $69 per month but costs $828 more in total interest. Extending from 48 to 72 months saves more per month but costs even more overall. The monthly savings feel significant; the total interest difference is what actually determines whether the longer term is worth it.
Does sales tax affect my auto loan amount?
Yes — in most states, sales tax is applied to the vehicle price and is typically rolled into the financed amount rather than paid separately upfront. This calculator applies the tax rate to the vehicle price before subtracting the down payment and trade-in, which produces a more accurate financed amount. On a $30,000 car with 8% sales tax, the taxed price is $32,400 — meaning you finance $2,400 more than the sticker price if you have no down payment. That additional amount increases both the monthly payment and total interest paid.