Car Loan Calculator
Monthly auto payment from price, down payment, trade-in, rate, term, and tax — with the amount financed.
Updated
Added to the financed amount. Leave at 0 to skip.
Monthly payment
$495.03/mo
$25,000.00 financed
- Amount financed
- $25,000.00
- Monthly payment
- $495.03
- Total interest
- $4,701.80
- Total cost (down + payments)
- $34,701.80
Estimates for general information, not financial advice.
In short
How much is the monthly payment on a car loan?
Finance (price − down − trade-in) × (1 + tax), then amortise it: payment = F × r(1 + r)^n ÷ [(1 + r)^n − 1] with r the monthly rate. A $30,000.00 car with $5,000.00 down at 7% over 60 months finances $25,000.00 and costs $495.03 a month, $4,701.80 of it interest.
In most states the sales tax is financed rather than paid up front, so an 8% rate here would lift the same payment to $534.63 and add interest on the tax as well.
How to use the car loan calculator
Start with the vehicle price, then subtract what you bring to the deal. The defaults model a common case: a $30,000.00 car with $5,000.00 down, no trade-in, at 7% over 60 months finances $25,000.00 and lands at $495.03 a month, with $4,701.80 of interest over the five years.
Both the down payment and a trade-in lower the amount you actually borrow, so raising either shrinks the payment before the interest rate enters the maths at all. Change any input and the result updates immediately, so you can watch each lever move the number.
Everything runs in your browser, so you can sit in a dealership and check a quoted payment against the arithmetic without anyone seeing what you typed.
$495.03
Monthly payment
$25,000.00 financed at 7% over 60 months
$4,701.80
Total interest
over the five years
$25,000.00
Amount financed
$30,000.00 price minus $5,000.00 down
This is where a car loan differs from a plain personal loan, and the difference is the point of the tool. With a generic loan you borrow a number and pay it back.
Borrowing a flat amount instead?
A personal or student loan has no price, trade-in or financed tax to strip out first. The loan payment calculator amortises the plain version of exactly this arithmetic.
Open the loan payment calculator →A car deal starts from the negotiated price, your down payment and trade-in come off the top, and in most states the sales tax goes the other way: it is added to the amount you finance rather than paid separately at signing. That tax quietly raises the payment, because you are borrowing it too and paying interest on it for the full term.
- Amount financed, no tax
- $25,000.00
- Sales tax at 8%
- + $2,000.00
- Amount financed with tax
- $27,000.00
Keep the defaults otherwise and the payment climbs from $495.03 to $534.63, and the total interest rises from $4,701.80 to $5,077.94. You are paying interest on the tax for five years.
A widely cited rule of thumb is the 20/4/10 guideline: put about 20% down, finance for no longer than four years, and keep total monthly vehicle costs, meaning the payment plus insurance, fuel, and upkeep, under about 10% of your gross income. It is a guideline rather than a law, and it is deliberately conservative, but it is a useful sanity check.
Run it on the default car and it holds up: 20% of $30,000.00 is $6,000.00 down, which finances $24,000.00, and over 48 months at 7% that is $574.71 a month with $3,586.07 of interest. Compare that to the 60-month version and you pay $79.68 more each month to save $1,115.72 in interest and own the car outright a year sooner.
Do
- Enter the negotiated price, including dealer fees the contract rolls into the amount financed.
- Subtract the down payment and trade-in, since both cut principal before interest applies.
- Enter your own tax rate when your state finances the sales tax rather than collecting it.
- Compare terms on total interest, because a dealer can lower any payment by stretching it.
Don't
- Use the sticker price when the contract is written against a negotiated figure.
- Assume the tax is settled at signing, as most states add it to what you borrow.
- Read the 20/4/10 figures as a rule, since it is a conservative guideline rather than law.
- Expect the payment maths to see depreciation, which is what decides when you are underwater.
The same $25,000.00 financed at 7% across every term the slider allows. The payment column is what the dealer will quote you; the last two columns are what the longer term actually costs. This is the trade-off a payment-first conversation never shows.
| Term | Monthly payment | Total interest | Total of all payments | Extra interest versus 36 months |
|---|---|---|---|---|
| 12 months | $2,163.17 | $958 | $25,958 | −$1,831 |
| 18 months | $1,467.12 | $1,408 | $26,408 | −$1,381 |
| 24 months | $1,119.31 | $1,864 | $26,864 | −$926 |
| 30 months | $910.80 | $2,324 | $27,324 | −$465 |
| 36 months | $771.93 | $2,789 | $27,789 | baseline |
| 42 months | $672.86 | $3,260 | $28,260 | +$471 |
| 48 months | $598.66 | $3,735 | $28,735 | +$946 |
| 54 months | $541.04 | $4,216 | $29,216 | +$1,427 |
| 60 months | $495.03 | $4,702 | $29,702 | +$1,912 |
| 66 months | $457.46 | $5,192 | $30,192 | +$2,403 |
| 72 months | $426.23 | $5,688 | $30,688 | +$2,899 |
| 78 months | $399.86 | $6,189 | $31,189 | +$3,400 |
| 84 months | $377.32 | $6,695 | $31,695 | +$3,905 |
What a longer term really costs
Be careful with the long terms the slider allows. Stretching the same $25,000.00 from 36 months to 84 drops the payment from $771.93 to $377.32, which is why dealers offer it, but the interest rises from $2,789.39 to $6,694.63. The reference table above carries the whole ladder. Treat every figure here as a general-information estimate; your actual rate, fees, and tax treatment depend on the lender and your state.
Read it: The 84-month version saves $394.61 a month against the three-year loan and costs $3,905.24 more in interest.
Values from the reference table above, rounded to the nearest dollar.
The formula, worked line by line
A car loan is the standard amortisation formula with a car-shaped front end bolted on. The price is reduced by your down payment and trade-in, then in most states the sales tax is added back to whatever is left, and that sum is the amount financed. Only then does the payment maths begin, and it runs on the financed figure rather than on the sticker price.
As with any monthly loan, r in the formula is the monthly rate, so the quoted annual rate is divided by twelve before it reaches the exponent, and the term is already expressed in months. Getting that division wrong is the classic error, and it inflates the answer dramatically rather than subtly.
financed = (price − down − trade-in) × (1 + tax% ÷ 100)
i = rate ÷ 12 ÷ 100 n = term in months
payment = financed × i × (1 + i)^n ÷ ((1 + i)^n − 1)
(if i = 0 → payment = financed ÷ n)- Vehicle price
- $30,000.00
- Down payment
- − $5,000.00
- Amount financed
- $25,000.00
- 60 payments of $495.03
- $29,701.80
- Total interest
- $4,701.80
At 7% the monthly rate is i = 0.07 ÷ 12 = 0.0058333, and over n = 60 months the formula gives the $495.03 payment. The total out of pocket, counting the down payment, is $34,701.80.
Each input does something distinct. The down payment and trade-in cut the financed amount dollar for dollar before any interest applies, so they reduce both the payment and the interest. Sales tax pushes the other way by enlarging what you borrow. The rate scales the cost of whatever you borrowed.
The term decides how many payments share the load, and it is the only lever that lowers the payment while raising the total cost: 36 months on $25,000.00 at 7% costs $771.93 a month and $2,789.39 in interest, while 84 months costs $377.32 a month and $6,694.63.
That is also where negative equity comes from. A long term keeps the balance high in exactly the years a new car loses value fastest, so for a stretch of the loan the payoff can exceed what the car would sell for. Nothing in this calculator models depreciation, because that depends on the specific vehicle, its mileage, and the used market, so treat the payment as arithmetic and the equity question as a separate judgement.
Questions people ask
How is a car loan different from a regular loan?
A car loan starts from the vehicle price rather than a flat amount you choose to borrow. Your down payment and trade-in both come off the price and lower what you finance, while sales tax in most states is added to the financed amount instead of paid separately at signing. Because the tax is borrowed too, it raises the payment and you pay interest on it for the whole term. After that front end, the payment maths is the same amortisation any fixed-rate loan uses.
How does sales tax change my car payment?
In most states the sales tax is added to the amount you finance, so you borrow it and pay interest on it. Take the defaults: $30,000.00 minus $5,000.00 down finances $25,000.00 at 7% over 60 months for a $495.03 payment and $4,701.80 of interest. Add 8% sales tax and the financed amount becomes $27,000.00, lifting the payment to $534.63 and the interest to $5,077.94. Rules differ by state, so check how yours treats the tax before assuming it is financed.
How much should I put down on a car?
A commonly cited rule of thumb is the 20/4/10 guideline: about 20% down, no more than four years of financing, and total monthly vehicle costs including insurance, fuel, and maintenance under about 10% of gross income. On the default car that means $6,000.00 down, financing $24,000.00 over 48 months at 7%, which is $574.71 a month and $3,586.07 of interest. That is $79.68 more each month than the 60-month version but $1,115.72 less interest overall.
Is a longer car loan term a good idea?
A longer term lowers the monthly payment and raises the total cost. On $25,000.00 at 7%, 36 months is $771.93 a month and $2,789.39 of interest, 60 months is $495.03 and $4,701.80, and 84 months is $377.32 and $6,694.63. So the 84-month version saves $394.61 a month against the three-year loan and costs $3,905.24 more in interest. Cars also depreciate faster than a long balance falls, which is where negative equity comes from.
What does it mean to be underwater on a car loan?
Being underwater, or having negative equity, means you owe more on the loan than the car is currently worth. It happens when a small down payment and a long term leave the balance falling more slowly than the car depreciates. It matters most if you sell, trade in, or total the car, because the payoff exceeds the value you get back and you cover the difference yourself. A larger down payment and a shorter term both shrink the period in which that gap can exist.
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