Auto Loan Calculator

A $25,000 car loan at 6% APR over 60 months costs $483.32 a month. You pay $3,999.20 in interest and $28,999.20 in total. Stretch the same loan to 84 months and the payment drops to $365.21, which feels better, but the interest rises to $5,677.64. That is the whole subject in two sentences: the monthly number is easy to move, and moving it usually costs you.

This guide works through how a car loan payment is calculated, what each month's payment is actually made of, what "EMI" means and why it is the same arithmetic, how boat, ATV, motorcycle and RV loans differ, why your lender insists on more than liability insurance while it holds a lien, and the one mistake that costs more than all the others put together: rolling negative equity from one car into the next. Every figure below comes out of the Auto Loan Calculator on this page, so you can reproduce any of them.

How to calculate a car loan payment

There is one formula, and every payment in this guide comes out of it. It is the standard amortization formula, the same one a mortgage uses:

Payment = P × r × (1 + r)^n ÷ ((1 + r)^n − 1)

where P is the amount financed, r is the APR divided by 12, and n is the term in months.

Worked through on a $25,000 loan at 6% APR over 60 months:

• Monthly rate: 6% ÷ 12 = 0.5%, or 0.005
• Growth factor: 1.005 to the power of 60 = 1.348850
• Numerator: $25,000 × 0.005 × 1.348850 = $168.606
• Denominator: 1.348850 − 1 = 0.348850
• Payment: $168.606 ÷ 0.348850 = $483.32

Multiply the payment by the term to get the total of payments, $483.32 × 60 = $28,999.20, and subtract the amount financed to get the interest, $28,999.20 − $25,000 = $3,999.20.

Two things follow from the shape of that formula. The payment moves in a straight line with the amount borrowed, so doubling the loan doubles the payment exactly. It does not move in a straight line with the term, which is why the jump from 36 to 48 months saves far more per month than the jump from 72 to 84 does.

What your monthly car payment is actually made of

Every payment is the same size, but the split inside it changes every single month. Interest is charged on the balance you still owe, so it is largest at the start, when the balance is largest, and it shrinks as the balance falls. Principal takes up whatever is left.

On that $25,000 loan at 6% over 60 months, the payment is $483.32 throughout:

Payment number	Interest portion	Principal portion	Balance after
1	$125.00	$358.32	$24,641.68
2	$123.21	$360.11	$24,281.57
12	$104.79	$378.53	$20,579.93
30	$69.24	$414.08	$13,433.43
60	$2.40	$480.92	$0.00

The first month's interest is the easiest number in the whole subject to check for yourself: $25,000 × 6% ÷ 12 = $125.00. Everything after that is the same calculation on a smaller balance.

Notice the halfway point. After 30 payments, half the term, you have paid $14,499.60 but the balance has only fallen from $25,000 to $13,433.43. You have cleared 46% of the loan with 50% of the payments. That gap is small on a 60 month loan and much wider on an 84 month one, and it is the mechanical reason long loans leave people owing more than the car is worth.

If you want to see what happens when you throw extra money at the balance, the Loan Payoff Calculator handles extra payments and shows how many months they remove.

What gets financed: price, sales tax, fees, down payment and trade-in

The amount the payment is calculated on is not the sticker price. It is:

Amount financed = vehicle price + sales tax + fees − down payment − trade-in

Sales tax in most US states is charged on the price net of your trade-in, which is why a trade-in is often worth more than its cash value. Some states tax the full price regardless, so confirm the rule where you register the car. Title, registration and dealer documentation fees are usually rolled into the loan rather than paid up front, which means you pay interest on them for the whole term.

A worked example. Suppose the car is $30,000, your trade-in is worth $8,000, your state charges 7% sales tax on the net price, fees come to $600, and you put $3,000 down:

• Taxable amount: $30,000 − $8,000 = $22,000
• Sales tax: $22,000 × 7% = $1,540
• Amount financed: $30,000 + $1,540 + $600 − $3,000 − $8,000 = $21,140
• Payment at 6% over 60 months: $408.70, with $3,382.00 of interest

The tax rate above is an assumption for the example, not a national figure. Rates vary by state and often by county and city, so look yours up and enter it, or check it in the Sales Tax Calculator first. The auto loan calculator has a sales tax field and applies it to the price after the trade-in, exactly as above.

Car loan payment by term: 36, 48, 60, 72 and 84 months

The same $25,000 at 6% APR, with nothing changed except how long you take to repay it:

Term	Monthly payment	Total interest	Total paid
36 months	$760.55	$2,379.80	$27,379.80
48 months	$587.13	$3,182.24	$28,182.24
60 months	$483.32	$3,999.20	$28,999.20
72 months	$414.32	$4,831.04	$29,831.04
84 months	$365.21	$5,677.64	$30,677.64

Read the first and last rows together. Going from 36 to 84 months cuts the payment by $395.34, slightly more than half, and raises the interest by $3,297.84, which is roughly 2.4 times as much. Each extra year of term buys a smaller payment reduction than the year before it while adding a similar chunk of interest, so the deal gets steadily worse the further you stretch.

This is why a dealer can hit almost any monthly payment you name without lowering the price by a cent. Negotiate the out-the-door price and your APR. Choose the term afterwards, and compare the total paid column rather than the monthly one.

How much does 1% on the APR change the car payment?

Less than most people expect on the monthly figure, and more than most people expect on the total. The same $25,000 over 60 months:

APR	Monthly payment	Total interest	Total paid
4%	$460.41	$2,624.60	$27,624.60
5%	$471.78	$3,306.80	$28,306.80
6%	$483.32	$3,999.20	$28,999.20
7%	$495.03	$4,701.80	$29,701.80
8%	$506.91	$5,414.60	$30,414.60
9%	$518.96	$6,137.60	$31,137.60
10%	$531.18	$6,870.80	$31,870.80

Each percentage point adds roughly $12 a month and roughly $700 in interest on a loan this size. That is the value of getting pre-approved by your own bank or credit union before you walk into a dealership: you arrive with a rate to beat instead of accepting whatever the finance office offers, and two points of difference is worth about $1,400 over the term.

The rates in that table are a range for illustration, not a quote. What you are actually offered depends on your credit, the lender, the loan term and whether the car is new or used.

What is a car loan EMI calculator?

EMI stands for equated monthly instalment, and it is the term used across India and much of Asia for what North America and the UK call a monthly car payment. There is no difference in the arithmetic. An EMI is calculated with the amortization formula at the top of this page: equal payments, interest charged on the declining balance, principal making up the rest.

So a car loan EMI calculator and a car loan payment calculator are the same tool under two names. If you are working in rupees, pesos, dirhams or any other currency, enter your loan amount, your annual interest rate and your tenure in months, and read the result in your own currency. The calculator on this page labels its output with a dollar sign because it defaults to US formatting, but the formula is currency independent and the number is correct whatever unit you entered.

An example in EMI shape. A loan of 800,000 at 9.5% annual interest over a 60 month tenure gives an EMI of 16,801.49, a total of 1,008,089.40 repaid, and 208,089.40 of interest. Enter those three inputs and you get those three outputs, regardless of the currency you have in mind.

Two vocabulary notes that trip people up when comparing tools. Tenure is the term, the number of months. And some lenders quote a flat rate rather than a reducing balance rate: a flat rate charges interest on the original amount for the whole term, so the same headline percentage produces a much higher real cost. This calculator, like almost every payment calculator, uses the reducing balance method. If your lender quotes a flat rate, ask for the equivalent APR before you compare anything.

Boat loan calculator: why boat and RV terms run so much longer

The payment formula does not change for a boat or a motorhome. What changes is the term, and the effect of that is large.

Car loans usually top out around 72 or 84 months. Loans on larger boats and RVs commonly run far longer, and on the biggest amounts they can be written over a decade or more. The reason is not generosity. It is that the amounts are bigger and the payment would be unaffordable otherwise, and lenders are willing to write longer paper because these are titled, registered assets the lender can secure a lien against and repossess, much like a car. Larger loans are often structured more like a property loan: bigger deposits, marine or RV specialist lenders rather than the dealer down the road, sometimes a survey or inspection requirement, and on the largest boats a chattel mortgage or preferred ship mortgage rather than a plain retail instalment contract.

Here is what a long term does to $45,000 financed, assuming 7% APR for illustration:

Term	Monthly payment	Total interest	Total paid
60 months	$891.05	$8,463.00	$53,463.00
84 months	$679.17	$12,050.28	$57,050.28
120 months	$522.49	$17,698.80	$62,698.80

The 120 month payment is 41% lower than the 60 month payment, and the interest is 109% higher. On that 10 year loan you still owe $34,618.59 after three years of payments, having paid $18,809.64 in. A boat or RV that has depreciated over the same three years can easily be worth less than that, which is the same negative equity problem cars have, stretched over a longer period.

One practical limit: this calculator accepts a term of up to 120 months. If your lender is quoting 15 or 20 years on a large marine loan, the arithmetic is identical but you will need a tool without that cap, and the Mortgage Calculator handles those longer horizons since it is built for 15 and 30 year terms.

Running costs are the other half of a boat or RV decision and none of them appear in a loan payment: moorage or storage, winterisation, insurance, haul-out, and fuel. Budget those separately before you decide what payment you can carry.

ATV loan calculator: how quad, motorcycle and powersports financing differs

ATVs, side-by-sides, motorcycles and jet skis sit at the opposite end. The amounts are small, the terms are short, usually somewhere between 24 and 60 months, and a lot of the financing is arranged at the dealership through a manufacturer's finance arm or a powersports lender rather than a bank.

Three things to watch, none of which the payment formula shows you:

Promotional financing has conditions. Manufacturer offers often pair a low or zero rate with a higher purchase price, or with a shorter term than you wanted, and the low rate usually depends on top-tier credit. Ask what the price is with and without the promotional rate, then run both through the calculator and compare the total paid.

Deferred interest is not the same as no interest. Some powersports promotions defer interest rather than waive it, which means the interest accrues from day one and is added to the balance if the full amount is not cleared by the end of the promotional window. Read which one you have been offered.

Short terms make the rate matter less and the price matter more. Over a short term there is simply not much time for interest to accumulate, so negotiating $500 off the price beats shaving a point off the rate.

A $12,000 ATV at 9% APR for illustration:

Term	Monthly payment	Total interest	Total paid
24 months	$548.22	$1,157.28	$13,157.28
36 months	$381.60	$1,737.60	$13,737.60
48 months	$298.62	$2,333.76	$14,333.76
60 months	$249.10	$2,946.00	$14,946.00

Registration and tax treatment for off-road vehicles varies by state and some are not taxed the way a road car is, so check before you assume the sales tax field applies to your purchase.

Auto loan insurance: why liability only is not enough while there is a lien

Searches for an "auto loan liability insurance calculator" are usually looking for one of two things: what insurance a financed car has to carry, or what the car really costs per month once insurance is included. There is no single calculator that returns a premium, because premiums are individually rated on your driving record, location, age, the vehicle and your claims history. Only a quote gives you that number. But the requirement is clear and the effect on the monthly cost is easy to work out.

State minimum liability covers other people, not your car. Liability insurance pays for the damage you cause to someone else. If your financed car is destroyed, liability pays nothing toward it, and you would still owe the lender the full remaining balance on a car you no longer have.

That is why lenders require comprehensive and collision. The lender holds a lien on the vehicle, which means the car is the collateral for the loan. Comprehensive and collision cover physical damage to that collateral: collision for crashes, comprehensive for theft, fire, flood, hail and similar. The lender is listed as the loss payee, so the insurer pays the lender first. Almost every finance contract requires this coverage for as long as the lien exists, along with a maximum deductible. If your policy lapses, the lender can buy force-placed insurance and add the cost to your loan, which is typically much more expensive than arranging your own and covers the lender's interest rather than yours. Once the loan is paid off the lien is released and the choice of coverage becomes yours again.

Gap insurance covers the difference between the payout and the balance. If the car is written off, a comprehensive or collision claim pays the car's actual cash value at that moment, not what you paid and not what you owe. When the balance is higher than the value, you are responsible for the difference. Gap insurance, sometimes sold as guaranteed asset protection, covers that shortfall.

A worked example on a total loss. Suppose you financed $30,000 at 6% over 72 months. After 18 payments you have paid $8,949.42 and your balance is $23,477.75. If the insurer settles at an actual cash value of $20,500, the claim clears $20,500 of the loan and leaves you owing $2,977.75 on a car that no longer exists. Gap insurance pays that $2,977.75. Without it, you pay it, usually while also trying to fund a replacement car.

That settlement figure is an assumption for the illustration. Real actual cash value depends on the model, mileage, condition and local market, which is what valuation guides are for. What is not an assumption is the balance: the calculator gives you that, and the gap only exists while the balance runs ahead of the value.

What this does to the real monthly cost. Insurance is not optional on a financed car, so the honest monthly number is the loan payment plus the premium, not the payment alone. Take that $30,000 loan over 72 months at $497.19 a month. Get a real quote for full coverage on that exact vehicle, divide the annual premium by twelve, and add it. If comprehensive and collision cost meaningfully more than liability alone on the car you are considering, that difference belongs in the decision, and it is one of the reasons a cheaper, less repair-costly car can be cheaper twice over.

Trade-in equity and negative equity: what happens when you roll one loan into the next

This is the most expensive mistake in car buying, and it is almost invisible in the paperwork because it arrives disguised as a lower price.

Your equity is what the car is worth minus what you still owe on it. Worth $16,000 with a $12,000 balance is $4,000 of positive equity, and it acts exactly like a cash down payment on the next car. Worth $13,500 with an $18,000 balance is $4,500 of negative equity, and someone has to pay it. The dealer will offer to roll it into the new loan.

Here is what rolling it costs. New car $30,000, $3,000 down, 6% APR, 72 months:

	Clean deal	With $4,500 rolled in
Amount financed	$27,000.00	$31,500.00
Monthly payment	$447.47	$522.05
Total interest	$5,217.84	$6,087.60
Total paid	$32,217.84	$37,587.60

The payment rises $74.58 a month. The total paid rises $5,369.76, which is the $4,500 you owed plus $869.76 of interest charged on it. You are now paying interest on a car you no longer own, for six years, and you started the new loan already underwater because $4,500 of the balance is not attached to anything you can sell.

Then it repeats. Three years into that rolled loan the balance is $17,160.02. If the car is worth less than that, and a car carrying rolled-in debt very often is, trading again means rolling a bigger number into a longer loan, and the cycle tightens each time.

How to get out of it, in rough order of preference. Keep the car and keep paying until the balance drops below the value, which is usually the cheapest option by a wide margin. Pay the shortfall in cash at trade-in so it never enters a loan. Sell privately rather than trading in, since private sale prices are typically higher than trade-in offers and the extra goes straight against the balance. If you have to refinance, do it on a shorter term rather than a longer one. The Loan Payoff Calculator shows how quickly extra payments close the gap, and even a modest extra amount each month moves the crossover point forward by months.

The prevention is simpler than the cure: a larger down payment, the shortest term you can carry, and not trading out of a car early. Negative equity is almost always the product of a long term and a small deposit meeting ordinary depreciation.

How to lower your car payment without making the loan worse

• Put more down. It reduces the amount financed directly, which reduces both the payment and the interest, and it is the only lever that improves every number at once.
• Take the shortest term you can genuinely afford. If the payment only works at 84 months, the honest conclusion is usually that the car is too expensive, not that the term is too short.
• Get pre-approved before you shop. A rate from your own bank or credit union is a rate the dealer has to beat, and the table above shows what a couple of points is worth.
• Negotiate the out-the-door price, never the monthly payment. A payment target can be met by lengthening the term while the price stays exactly where the dealer wants it.
• Decline financed add-ons. Extended warranties, paint protection and similar products added to the loan are borrowed money that accrues interest for the full term. If you want one, price it separately and pay for it separately.
• Check whether the loan has a prepayment penalty. Most US auto loans are simple interest with no penalty, which means extra payments go straight to principal, but read the contract rather than assuming.
• Refinance only if the new term is not longer. A lower rate over a longer term can still cost more overall, so compare total paid, not the payment.

The bottom line

A car loan payment is set by three things: the amount financed, the APR, and the term. The formula never changes, whether the lender calls it a monthly payment or an EMI, and whether the thing you are financing is a sedan, a quad bike or a motorhome. The term is where the money goes. A longer one always lowers the payment and always raises the total, and it is what puts drivers underwater and sets up the next trade with negative equity attached.

Enter your real price, your real trade-in, your state's tax rate and the rate you have actually been quoted into the Auto Loan Calculator, then compare the total of payments across two or three terms before you sign anything. Add a real insurance quote to the monthly figure so you are comparing the cost of owning the car, not just the cost of borrowing for it. Tax rules, lender requirements and insurance rules vary by state and by lender, so confirm the specifics for yours.