Auto Loan Calculator

The sticker says $30,000. The loan says something else entirely.

Use this free auto loan calculator to find your monthly car payment from the price, trade-in value, interest rate, and loan term. Enter the numbers the dealer keeps rearranging on the little four-square sheet and see the payment they were trying to make you stop looking at.

Car financing math is simple amortization with an emotional multiplier. The payment looks small because the term is long; the term is long because the payment has to look small. We calculate the honest number and note how much of it is interest.

What This Auto Loan Calculator Does

Calculates the monthly payment on a car loan using standard amortization
Subtracts your trade-in (or down payment — same math) from the price
Lets you compare 36, 48, 60, 72, and 84-month terms to see what "lower payment" really costs
Gives you the one number to know before walking into a dealership: what you can actually afford per month

How to Use the Auto Loan Calculator

Inputs:

Price — the negotiated vehicle price. Add tax, title, and fees here if you plan to finance them
Trade-In — trade-in value or cash down payment (both reduce the amount financed)
Rate — APR in %. Check your pre-approval; dealers mark up rates
Months — loan term. 60 is common; 72–84 is common and unwise

Steps:

Enter price and trade-in/down payment
Enter the APR you have actually been offered, not the one in the ad
Pick a term and click Calculate
Multiply the payment by the months and subtract the amount financed — that is your total interest. Then try 48 months.

How the Calculation Works

Payment = L × [ r(1+r)^n ] ÷ [ (1+r)^n − 1 ] L = Price − Trade-In · r = APR ÷ 12 ÷ 100 · n = months

This is the standard amortization formula used for car loans, mortgages, and personal loans
Total interest = Payment × n − L. Longer terms lower the payment and raise this number, every time
Rule of thumb: total car costs (payment + insurance + fuel) under 15–20% of take-home pay; the 20/4/10 rule says 20% down, 4-year term, 10% of gross income

Worked Example: $32,000 car, $5,000 trade-in, 6.5% APR, 60 months

L = 32,000 − 5,000 = $27,000 · r = 0.065 ÷ 12 = 0.005417 · n = 60
(1.005417)^60 = 1.3829
Payment = 27,000 × (0.005417 × 1.3829) ÷ 0.3829 = $528.29/month
Total paid: 528.29 × 60 = $31,697 → interest = $4,697. Same loan at 72 months: $453/mo but $5,633 interest. The extra year costs you $936 for the privilege of a smaller number.

Tips (From People Who Have Made These Mistakes)

Get pre-approved at a bank or credit union before shopping. It turns "what payment do you want?" into "here is my rate, beat it"
Negotiate the price, not the payment. Dealers can hit any payment by stretching the term
Avoid financing add-ons (extended warranty, paint protection) — you will pay interest on them for five years
If the payment only works at 84 months, the car does not work. Check the car lease calculator or a cheaper car

Frequently Asked Questions

How is a car payment calculated?

With the amortization formula: Payment = L × r(1+r)^n ÷ ((1+r)^n − 1), where L is the amount financed, r the monthly rate, and n the number of months. This calculator does it for you; the example above walks through it.

What is a good APR for a car loan?

It depends on credit and market rates. Excellent credit on a new car has recently seen 5–7%; used cars run higher; subprime can exceed 15%. Anything above ~10% deserves a second opinion from a credit union.

Should I get a 60 or 72-month car loan?

Shorter if you can afford it. 72+ months means paying interest longer and being upside-down (owing more than the car is worth) for years. If 60 months is a stretch, the answer is usually a less expensive car.

How much should I put down on a car?

Aim for 20% on new, 10% on used. It offsets immediate depreciation and lowers the payment and total interest. A trade-in counts toward this.

Does the calculator include taxes and fees?

Only if you add them to the price field. Sales tax, registration, and doc fees typically add 7–10% and are often rolled into the loan — include them to see the real payment.

Mini Roast Disclaimer

We roast the number, not you. The car is lovely. The 84-month term is the problem, and it knows.

Reality Check

This calculator computes principal and interest only. Real ownership adds insurance, fuel, maintenance, and depreciation — often as much again as the payment. Rates quoted here assume a fixed APR and no prepayment penalties; check your contract. Pre-approval and price negotiation will save you more than any calculator.

Auto Loan Calculator

Inputs