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Auto Loan Calculator.
Monthly car payment the way a dealership's desk calculates it: your state's sales tax, the trade-in tax credit where your state allows it, rebates, fees and what you still owe on the trade.
Estimates for planning only. Your lender, dealer or tax authority sets the real numbers, and rates, fees and rules change. This is not financial, tax or legal advice. Nothing you type here leaves your browser. Terms.
Where the money goes
Total cost of the vehicle over the life of the loan, by piece.
Loan balance over time
Payment schedule
Guide
How to use the Auto Loan Calculator
- Enter the Vehicle price: the negotiated selling price, not the sticker and not the "out the door" number. Tax and fees get their own fields.
- Enter your Down payment in cash, then the Trade-in value you expect to be offered. If you still owe on that car, put the payoff balance in the Amount still owed on trade-in field.
- Enter any Manufacturer rebate. This is cash the automaker takes off the price, not a dealer discount.
- Pick your State. The dropdown sets a default Sales tax rate and applies your state's trade-in tax credit rule (the Trade-in tax credit dropdown lets you override it). Adjust the rate if your city or county adds to it, and enter your Title, registration & dealer fees.
- Leave Finance taxes and fees into the loan checked to roll them into the loan. Uncheck it if you'll pay them in cash at signing.
- Enter the Interest rate (APR) and the Loan term in months, and set the First payment date so the payoff date and schedule follow the calendar.
- Read the headline Monthly payment, then check the Payment schedule and the balance chart. Switch the schedule between Yearly and Monthly to see how fast the balance falls.
How the math works
Two calculations are stacked. First the calculator figures out how much you're borrowing. Then it turns that loan into a fixed monthly payment.
The amount financed starts with the price, subtracts everything that reduces it (down payment, trade-in value, rebate), adds back anything you still owe on the trade, then adds sales tax and fees if you chose to finance them. Sales tax is charged on the taxable amount, which in most states is the price minus your trade-in credit, and minus the rebate in states that don't tax rebates. The State dropdown sets the rebate rule for you; the checkbox Tax is charged before the rebate is subtracted (rebate is taxed) lets you override it.
The loan is then amortized: the same payment every month, with interest charged on the remaining balance, so early payments are mostly interest and later ones mostly principal.
The formula
Payment = P × r ÷ (1 − (1 + r)^−n)
P is the amount financed. r is the monthly rate, the APR divided by 12 (6.9% becomes 0.069 ÷ 12 = 0.00575). n is the number of monthly payments. If the APR is 0%, the payment is simply P ÷ n.
Amount financed = Vehicle price − Down payment − Trade-in value + Amount still owed on trade-in − Manufacturer rebate + (Sales tax + fees, if financed)
Worked example
You're buying a $35,000 vehicle with $3,000 down and an $8,000 trade-in you own outright. There's a $1,000 manufacturer rebate, your state charges 7% sales tax and gives the full trade-in credit, and you roll $500 in title, registration and dealer fees into a 60-month loan at 6.9% APR.
| Step | Math | Result |
|---|---|---|
| Taxable amount | 35,000 − 8,000 − 1,000 | $26,000.00 |
| Sales tax | 26,000 × 7% | $1,820.00 |
| Amount financed | 35,000 − 3,000 − 8,000 − 1,000 + 1,820 + 500 | $25,320.00 |
| Monthly payment | 25,320 × 0.00575 ÷ (1 − 1.00575^−60) | $500.17 |
| Total of payments | 500.17 × 60 | $30,010.36 |
| Total interest | 30,010.36 − 25,320 | $4,690.36 |
Your first payment is $145.59 of interest (25,320 × 0.00575) and $354.58 of principal. By the last payment, almost all of the $500.17 is principal.
Now run the identical deal in a state with no trade-in credit. The taxable amount jumps to $34,000, tax to $2,380.00, and the amount financed to $25,880.00. The payment becomes $511.23 and total interest $4,794.09. The missing credit costs you $560 in tax and $11.06 a month.
The trade-in tax credit
In most states, when you trade a car in on the same transaction, you pay sales tax only on the difference between the new car's price and your trade-in's value. That's the trade-in tax credit. On an $8,000 trade at 7% it's worth $560, real money a private-party sale doesn't get you.
A handful of states don't allow the credit at all, and a few cap it at a fixed dollar amount. The State dropdown applies the right rule, and the table below shows which states do what.
Trade-in tax credit by state
How each state treats a trade-in when it taxes a dealer purchase. "Full credit" means the trade-in value is subtracted before tax. The rate shown is the state portion of the tax on a vehicle purchase (some states use a special vehicle tax instead of general sales tax); "Yes" under local means cities or counties add to it. "Rebates taxed" means tax is charged on the price before a manufacturer rebate is subtracted. Pick a state in the calculator above for the details and exceptions. Compiled from state revenue and motor-vehicle agency pages as of 2026-10-27; rules change, so confirm with the dealer’s paperwork.
| State | Trade-in credit | Vehicle tax rate | Local taxes added | Rebates taxed |
|---|---|---|---|---|
| Alabama | Full credit | 2% | Yes | Yes |
| Alaska | No sales tax | none | Yes | Unconfirmed |
| Arizona | Full credit | 5.6% | Yes | Unconfirmed |
| Arkansas | Full credit | 6.5% | Yes | Yes |
| California | No credit | 7.25% | Yes | Yes |
| Colorado | Full credit | 2.9% | Yes | Yes |
| Connecticut | Full credit | 6.35% | No | Unconfirmed |
| Delaware | No sales tax | none | — | No |
| District of Columbia | No credit | varies | No | Unconfirmed |
| Florida | Full credit | 6% | Yes | Yes |
| Georgia | Full credit | 7% | No | No |
| Hawaii | No credit | 4% | Yes | Yes |
| Idaho | Full credit | 6% | No | No |
| Illinois | Full credit | 6.25% | Yes | Yes |
| Indiana | Full credit | 7% | No | Yes |
| Iowa | Full credit | 5% | No | No |
| Kansas | Full credit | 6.5% | Yes | No |
| Kentucky | Full credit | 6% | No | No |
| Louisiana | Full credit | 5% | Yes | Unconfirmed |
| Maine | Full credit | 5.5% | No | Yes |
| Maryland | Full credit | 6.5% | No | Yes |
| Massachusetts | Full credit | 6.25% | No | No |
| Michigan | Capped ($12,000) | 6% | No | Yes |
| Minnesota | Full credit | 6.875% | No | No |
| Mississippi | Full credit | 5% | No | Yes |
| Missouri | Full credit | 4.225% | Yes | No |
| Montana | No sales tax | none | — | Unconfirmed |
| Nebraska | Full credit | 5.5% | Yes | No |
| Nevada | Full credit | 6.85% | Yes | Yes |
| New Hampshire | No sales tax | none | — | Unconfirmed |
| New Jersey | Full credit | 6.625% | No | Yes |
| New Mexico | Full credit | 4% | No | Unconfirmed |
| New York | Full credit | 4% | Yes | Yes |
| North Carolina | Full credit | 3% | No | Yes |
| North Dakota | Full credit | 5% | No | No |
| Ohio | New vehicles only | 5.75% | Yes | Yes |
| Oklahoma | No credit | 4.5% | No | Unconfirmed |
| Oregon | No sales tax | none | — | No |
| Pennsylvania | Full credit | 6% | Yes | No |
| Rhode Island | Full credit | 7% | No | No |
| South Carolina | Full credit | 5% (max $500) | No | Yes |
| South Dakota | Full credit | 4% | No | Unconfirmed |
| Tennessee | Full credit | 7% | Yes | Yes |
| Texas | Full credit | 6.25% | No | No |
| Utah | Full credit | 4.85% | Yes | No |
| Vermont | Full credit | 6% | No | Unconfirmed |
| Virginia | No credit | 4.15% | No | No |
| Washington | Full credit | 7% | Yes | Yes |
| West Virginia | Full credit | 6% | No | Yes |
| Wisconsin | Full credit | 5% | Yes | Yes |
| Wyoming | Full credit | 4% | Yes | No |
Before selling your old car privately for a few hundred more, do this math. If the credit beats the private buyer's premium, trading in wins.
Negative equity, rebates and the long-term trap
Owing more than the trade is worth
If you owe $10,000 on a car the dealer values at $8,000, you have $2,000 of negative equity, and it doesn't disappear. The full $10,000 payoff goes in the Amount still owed on trade-in field and is added to the new loan. In our example that pushes the amount financed from $25,320 to $35,320, the payment from $500.17 to $697.71, and total interest from $4,690.36 to $6,542.79. That's five years of interest on a car you no longer own.
Rebate or low APR
Automakers often make you choose: the cash rebate or a promotional rate. Run both and compare the Total cost of the vehicle line, not the payment. Keeping the $1,000 rebate at 6.9% gives a total cost of $41,010.36. Giving up the rebate for 1.9% APR gives $38,684.24, which is $2,326.12 better.
At 3.9% the low rate still wins, but by only $921.04. The bigger the loan and the longer the term, the more a low rate is worth.
Why a longer term feels cheaper and costs more
| Term | Monthly payment | Total interest |
|---|---|---|
| 48 months | $605.14 | $3,726.95 |
| 60 months | $500.17 | $4,690.36 |
| 72 months | $430.47 | $5,673.56 |
| 84 months | $380.91 | $6,676.45 |
Stretching the same $25,320 from 60 to 84 months cuts the payment by $119.26 and adds $1,986.09 of interest. It also keeps you underwater longer, because the car loses value faster than the balance falls early on. If the 60-month payment doesn't fit, look at a cheaper car, not a longer loan.
When to use the other calculators
Deciding between leasing and buying? Run the same car through the Auto Lease Calculator and compare total cost over the same months. The Amortization Calculator shows what extra payments do to a loan you already have, and the Loan Calculator works backward from the payment you can afford to the loan amount it buys.
What this calculator doesn't do
The results are estimates. The lender's contract and the dealer's buyer's order govern, and they may round differently, compute interest daily, or add products like GAP coverage and extended warranties that aren't in these fields. Tax rates, fee caps and trade-in credit rules change, so confirm the tax line on the paperwork before you sign.
It assumes a fixed rate with no prepayment penalty and no late payments, and it doesn't estimate insurance, fuel or depreciation.
Frequently asked questions
How is a car loan payment calculated?
The amount financed is multiplied by the monthly interest rate (APR divided by 12) and divided by 1 minus (1 plus the monthly rate) raised to the negative number of months. On $25,320 at 6.9% for 60 months that comes to $500.17 a month, of which $145.59 is interest in the first month.
Does a trade-in reduce the sales tax on a new car?
In most states yes: tax is charged on the price minus the trade-in value, so an $8,000 trade at 7% saves $560. A handful of states don't allow the credit and a few cap it, which is why the calculator asks for your state.
Should I take the rebate or the low APR?
Run both and compare the total cost of the vehicle, not the payment. In the example above, a $1,000 rebate at 6.9% costs $2,326.12 more over five years than skipping the rebate for 1.9% APR, but with a smaller loan or shorter term the cash can win.
What happens if I owe more than my trade-in is worth?
The shortfall, called negative equity, is added to the new loan. Owing $10,000 on a car valued at $8,000 adds $10,000 to the amount financed in the example and raises the payment from $500.17 to $697.71, so you are paying interest on a car you no longer own.
Is a 72- or 84-month car loan a bad idea?
It lowers the payment but raises the total interest and keeps you owing more than the car is worth for longer. Stretching the example loan from 60 to 84 months drops the payment by $119.26 a month and adds $1,986.09 in interest.
Should I finance the sales tax and fees or pay them in cash?
Paying them up front avoids interest on money that buys nothing you can resell. Financing the $2,320 of tax and fees in the example adds about $45.83 a month and $429.76 of interest over 60 months.
How accurate is this auto loan calculator?
It uses the standard amortization formula that lenders use, so the payment should match to within a few cents. The contract governs, and it may include products, daily interest accrual or local tax quirks that the calculator doesn't model.
Estimates for planning only. Your lender, dealer or tax authority sets the real numbers, and rates, fees and rules change. This is not financial, tax or legal advice. Nothing you type here leaves your browser. See the terms of use.
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