Cash Back or Low Interest Calculator
Dealers often make you choose between a cash rebate and a low APR on the same car. Enter both offers and this tool shows each one's monthly payment and total cost, then tells you which is cheaper and by how much.
The vehicle
How to use this calculator
1. Enter the vehicle and down payment
Start with the negotiated price and the cash you'll put down. The down payment is the same under both offers, so it doesn't change which one wins — but it does change the size of each payment.
2. Fill in Option A (the rebate)
Enter the cash-back amount the dealer is offering and the APR that comes with it. The rebate is subtracted from the amount you finance.
3. Fill in Option B (the low rate)
Enter the promotional low APR. This offer usually carries little or no rebate, so the full price minus your down payment is financed.
4. Compare monthly payment and total cost
The result highlights the cheaper deal by total cost and shows the dollar savings. Both monthly payments are shown too, since a low monthly figure can still cost more overall.
About cash back vs. low interest
Is a cash rebate or a low interest rate the better car deal?
It depends on the loan size and term. A rebate lowers the amount you finance up front, while a low APR cuts the interest you pay over time. This calculator works out the monthly payment and total cost of each so you can compare them directly.
Why does the longer or larger loan favor the low APR?
The more you borrow and the longer you borrow it for, the more total interest a higher APR adds. A one-time rebate is a fixed dollar amount, so on big, long loans the low-rate offer often wins even when the rebate looks tempting.
How total cost is figured
For each offer we find the financed amount, compute the standard amortized monthly payment, multiply it by the number of months, and add your down payment. Taxes, fees, and dealer add-ons aren't included — compare the two on the same out-the-door basis.