How to calculate your monthly car payment

Your monthly car payment depends on four things: the price of the car, how much you put down, the interest rate you get, and the length of the loan. The formula lenders use is straightforward—they divide the amount you're borrowing by the number of months, add interest charged each month on the remaining balance, and that's your payment.

If you borrow $20,000 at 6% interest over 60 months, your payment will be roughly $386 per month. If the same loan runs 72 months instead, it drops to about $333. If your interest rate is 10% instead of 6%, that same 60-month loan jumps to roughly $423. The three levers—loan amount, rate, and term—move your payment in predictable directions.

You can calculate this yourself with a basic car loan calculator (most banks and dealer websites have them), or you can work backward from a payment you can afford to see what price car fits your budget. The math is the same either way.

Key Takeaways

  • Your payment is determined by the loan amount, interest rate, and number of months—change any one and your payment changes.
  • A longer loan term (72 months instead of 60) lowers your monthly payment but costs you more in total interest.
  • Your interest rate depends on your credit score, the lender, and current market rates—shopping around can save hundreds of dollars over the life of the loan.
  • Your down payment reduces the amount you borrow, which directly lowers your monthly payment and the total interest you pay.
  • Your payment does not include insurance, registration, maintenance, or fuel—budget for those separately.

How down payment size changes your payment

A larger down payment means you borrow less money, which lowers your monthly payment. Put down $5,000 on a $25,000 car and you borrow $20,000. Put down $10,000 and you borrow $15,000. On a 60-month loan at 6%, that $5,000 difference cuts your payment by about $86 per month.

Down payment also affects the interest rate you're offered. Lenders see a larger down payment as lower risk, so they may offer you a better rate. A 0.5% rate reduction on a $15,000 loan over 60 months saves you roughly $40 per month. The combination of borrowing less and getting a better rate makes down payment one of the most powerful levers you control.

Most lenders want at least 10% down, though some will go lower. If you have less saved, consider waiting to buy or looking at used cars in a lower price range. Putting down less than 10% usually means paying a higher rate and possibly paying for gap insurance (which covers the difference if the car is totaled and you still owe money).

What interest rate you'll pay and where it comes from

Your interest rate depends on three things: your credit score, the lender you choose, and the current market. A credit score above 750 might get you 4% to 5%. A score between 650 and 700 might get you 7% to 9%. A score below 650 might get you 10% or higher, or you might not be approved at all.

Different lenders offer different rates for the same credit profile. Banks, credit unions, and online lenders often beat dealer rates by 1% to 3%. Get pre-approved by at least two or three lenders before you go to the dealership. Pre-approval shows you what rate you actually may have access to for and gives you negotiating power—dealers sometimes match or beat outside offers.

Market rates also shift. When the Federal Reserve raises its benchmark rate, car loan rates rise across the board. When rates fall, so do loan offers. You can't control the market, but you can control your credit score (pay bills on time, keep credit card balances low) and you can shop lenders instead of accepting the first offer.

How loan length affects what you pay each month and over time

A longer loan spreads the same amount of money over more months, so your payment gets smaller. A $20,000 loan at 6% costs $386 per month over 60 months but only $333 per month over 72 months. That's $53 less per month—but you're paying interest for 12 extra months, so the total interest you pay rises from about $3,160 to about $3,996. You save $636 in monthly payments but spend $836 more in interest.

The math gets worse at higher interest rates. At 10%, a 60-month loan costs $423 per month and $5,379 in total interest. A 72-month loan costs $366 per month but $6,352 in total interest—you save $57 per month but pay $973 more overall. The longer the loan, the more interest compounds.

Most car loans run 60, 72, or 84 months. Some lenders offer 96-month loans, which can push your payment down but leave you "upside down" (owing more than the car is worth) for years. Choose the shortest term you can afford—it costs less in the end.

What happens if you put down less than 10%

Lenders see a down payment below 10% as higher risk. You'll typically pay a higher interest rate—sometimes 1% to 3% more than someone putting down 20%. You may also be required to buy gap insurance, which costs $500 to $1,000 upfront or gets rolled into your loan payment.

Gap insurance protects you if the car is totaled before you've paid off the loan. If you owe $18,000 and the car is worth $15,000, gap insurance covers the $3,000 gap. Without it, your insurance company pays you the car's value and you still owe the lender the difference. With a small down payment, you're more likely to be underwater (owing more than the car is worth) early in the loan, so lenders require it.

If you can't put down 10%, consider buying a less expensive car or waiting until you've saved more. A smaller loan at a better rate costs less per month and less in total interest than a larger loan with a penalty rate and mandatory gap insurance.

How to estimate your payment before you go to the dealership

Use an online calculator with real numbers: the actual price of the car you want (not the sticker price—that's negotiable), the down payment you can afford, and the interest rate you've been pre-approved for. Most bank and credit union websites have calculators. Edmunds, Kelley Blue Book, and NerdWallet also have them.

Enter the loan amount (car price minus down payment), the interest rate, and the loan term. The calculator shows your monthly payment and total interest. Run it three ways: with your best-case rate (what you'd get with excellent credit), your realistic rate (what you've actually been pre-approved for), and your worst-case rate (what you might pay if your credit score is lower than you think).

This gives you a range. If your realistic payment is $350 per month and you can't afford that, don't go to the dealership expecting to negotiate your way down—the math doesn't work that way. Instead, look at cheaper cars, save for a larger down payment, or improve your credit score before you apply.

Why your actual payment might be higher than the calculator shows

The calculator shows the loan payment only. Your actual monthly cost includes insurance, registration, maintenance, and fuel. Insurance on a financed car is usually higher than on an older paid-off car because the lender requires full coverage (collision and comprehensive). Budget $100 to $200 per month depending on your age, location, and driving record.

Registration and taxes vary by state but often run $200 to $500 per year. Maintenance on a new car under warranty is minimal, but on a used car it can be $100 to $300 per month. Fuel depends on the car's efficiency and your driving—budget $150 to $300 per month for a typical commute.

Add these to your loan payment to see your true monthly cost. If your loan payment is $350 and insurance is $150, maintenance is $100, and fuel is $200, your actual monthly cost is $800. Make sure that fits your budget before you commit.

Frequently Asked Questions

Can I lower my payment by trading in my old car?

Yes. The trade-in value reduces the amount you need to borrow. If your old car is worth $5,000 and you're buying a $25,000 car, you borrow $20,000 instead of $25,000. That lowers your payment by roughly $86 per month on a 60-month loan at 6%. Get the trade-in value appraised independently before you go to the dealer—dealers often lowball trade-in offers.

What if I want to pay off the loan early?

Most car loans let you pay extra toward principal without penalty. Paying an extra $50 per month on a $20,000 loan at 6% over 60 months cuts about 6 months off the loan and saves roughly $600 in interest. Check your loan documents or ask your lender whether there's a prepayment penalty—some older loans have them, but most modern loans don't.

Does my credit score affect my payment?

Yes, through the interest rate. A higher credit score gets you a lower rate, which lowers your payment. The difference between a 750 score and a 650 score can be 2% to 4% in interest rate, which translates to $40 to $80 per month on a $20,000 loan. If your score is low, wait a few months to build it before you apply—it's worth the delay.

What's the difference between APR and interest rate?

APR (annual percentage rate) includes the interest rate plus fees the lender charges. The interest rate is just the cost of borrowing. On a car loan, they're usually close, but APR is the number to compare between lenders because it shows the true cost. A loan with a 6% interest rate might have a 6.2% APR if there's a $200 origination fee.

Can I negotiate my interest rate at the dealership?

Not directly—the rate is set by the lender based on your credit and the market. But you can negotiate the car's price, which affects how much you borrow. You can also walk away and use your pre-approval from a bank or credit union instead of the dealer's financing. Dealers sometimes match outside offers to keep the sale.