Work out your monthly car payment from vehicle price, down payment, trade-in, interest rate and term, with sales tax, total interest and a full amortization schedule.
Advanced: sales tax and extra fees
If you added another $2,000 of cash up front, here is how the monthly payment and the interest you pay over the full term would change.
Early payments are mostly interest, so the balance drops slowly at first and faster near the end. The marked point shows the halfway month of the term.
| Month | Payment | Interest | Principal | Balance |
|---|
For beginners: how to read this result
Start with a preset (new car, used car, or refinance with a trade-in) or type your own figures: vehicle price, down payment cash, trade-in value, any loan still owed on the trade-in, the interest rate and the term in months. The advanced section adds sales tax and other fees, plus a toggle for whether your region lets a trade-in reduce the taxable amount.
How the monthly payment is built
The taxable amount is the vehicle price, minus the trade-in value when the trade-in reduces tax. Sales tax is the taxable amount times the tax rate. The amount financed is the price, plus sales tax, plus other fees, minus the down payment cash, minus your trade-in equity (trade-in value minus the loan still owed on it). The monthly payment then spreads that financed amount over the term using a standard fixed-rate loan formula, so total interest is the sum of all payments minus the amount financed.
Trade-in equity and negative equity
Only the part of a trade-in worth more than its remaining loan lowers your new loan. If you still owe more on the trade-in than it is worth, that gap is added to the amount financed. When the financed amount ends up larger than the car price, the calculator shows a negative equity warning: you would owe more than the vehicle is worth from the first month.
Down payment what-if and the schedule
The what-if block shows how adding more cash up front lowers both the monthly payment and the total interest. The amortization schedule lists each month’s split between interest and principal, and the balance chart shows how the outstanding loan falls faster as the term progresses.
What is not included
This is a planning estimate, not a loan offer. It does not model variable rates, gap insurance, extended warranties bundled into the loan, dealer add-ons beyond the fees field, early payoff penalties or rebates. The exact interest rate depends on your credit profile and lender, and sales tax rules vary by region, so confirm every figure with your lender before signing.