Car Payment Calculator

Estimate your monthly car payment, total interest paid, and true cost of vehicle ownership. Compare loan terms and check if a car fits your budget.

For affordability calculation

Loan Details

Vehicle Price
$35,000
Down Payment
$5,000
Loan Amount
$30,000
Total Interest
$4,382
Monthly Payment
$573

Affordability & Cost

Payment % of Income(Manageable)
11.5%
Total Loan Cost
$39,382
Annual Cost of Ownership(payment + insurance + maintenance)
$8,876

Affordability Check

0%10%15%25%+

11.5%

Manageable

Financial experts recommend keeping your car payment below 10-15% of your monthly income.

Monthly Cost Breakdown

See how this car payment fits your budget

Your estimated payment is $573/month. See how it fits alongside your income, rent, savings, and other expenses in a complete financial simulation.

Try the Full Simulator

How Car Loan Payments Are Calculated

Car loan payments are calculated using an amortization formula. The loan amount is determined by subtracting your down payment and trade-in value from the vehicle price. Then, based on the interest rate (APR) and loan term, a fixed monthly payment is computed that will fully repay the loan by the end of the term.

The formula is: M = P[r(1+r)^n] / [(1+r)^n - 1], where P is the loan principal, r is the monthly interest rate (annual rate divided by 12), and n is the number of monthly payments. Like mortgages, early payments are mostly interest, and later payments are mostly principal.

New vs Used Car Financing

New Car

  • Lower interest rates (3-7% for good credit)
  • Rapid depreciation — 20-30% in first year
  • Full manufacturer warranty
  • Latest safety features and technology
  • 60% value loss over five years

Used Car (2-4 years)

  • Higher rates (5-10%+) but lower price
  • Steepest depreciation already occurred
  • CPO options offer reliability + value
  • Lower insurance premiums
  • Better overall value proposition

How to Get the Best Auto Loan Rate

1

Check your credit score first.

Your credit score is the single biggest factor in your interest rate. Scores above 740 qualify for the best rates. If your score is below 670, consider improving it before financing a vehicle.

2

Get pre-approved.

Apply for pre-approval from your bank, credit union, and at least one online lender before visiting dealers. Credit unions often offer the most competitive rates.

3

Keep the loan term short.

Shorter terms (36-48 months) usually come with lower rates than longer terms (72-84 months). Plus, you will pay far less in total interest.

4

Make a substantial down payment.

Putting 20% or more down reduces the lender's risk and can qualify you for a better rate. It also means you are less likely to be underwater on the loan.

5

Negotiate the price separately from financing.

Agree on the vehicle price first, then discuss financing. Dealers sometimes inflate the price to make a low monthly payment look attractive while extending the term.

The True Cost of Car Ownership

Your car payment is just one part of vehicle ownership costs. A comprehensive budget should include insurance ($100-$200/month), fuel ($125-$250/month), maintenance and repairs ($40-$100/month), registration and taxes, and depreciation. For a $35,000 new car, the total cost of ownership over 5 years can exceed $50,000 — well above the purchase price alone.

Insurance: $100-$200/month depending on coverage and driving record

Fuel: $125-$250/month depending on vehicle efficiency and commute

Maintenance and repairs: $40-$100/month averaged over ownership

Registration, taxes, and inspection fees vary by state

Depreciation: the biggest hidden cost, especially for new vehicles

To keep transportation costs manageable, financial advisors recommend the 20/4/10 rule: 20% down payment, no more than a 4-year loan, and total transportation costs under 10% of gross income. If a car does not meet this test, consider a less expensive vehicle or saving for a larger down payment.

See How Your Car Payment Fits Into Your Complete Budget

This calculator shows your monthly car payment. Trajectoryy's full simulator shows how that payment fits alongside your income, rent, savings, investments, and more — month by month for years into the future.

Start Simulating for Free

Frequently Asked Questions

How is a car payment calculated?
A car payment is calculated using the loan amount (vehicle price minus down payment and trade-in), the interest rate (APR), and the loan term in months. The formula uses amortization to determine a fixed monthly payment that covers both principal and interest. A longer loan term lowers your monthly payment but increases the total interest you pay.
What is a good interest rate for a car loan?
As of 2025, good interest rates are approximately 5-7% for new cars and 7-10% for used cars. Borrowers with excellent credit (750+) can qualify for rates as low as 3-5% for new vehicles. Rates vary significantly based on your credit score, the lender, whether the car is new or used, and the loan term.
How much should I spend on a car?
Financial experts recommend the 20/4/10 rule: put at least 20% down, finance for no more than 4 years (48 months), and keep total transportation costs (payment, insurance, gas, maintenance) under 10% of your gross monthly income. At minimum, your car payment alone should not exceed 10-15% of your monthly take-home pay.
Should I choose a longer or shorter loan term?
A shorter loan term (36-48 months) means higher monthly payments but significantly less total interest. A longer term (60-84 months) lowers monthly payments but can cost thousands more in interest and may lead to being 'underwater' (owing more than the car is worth). For example, a $30,000 loan at 6% costs $580/month over 60 months ($4,800 in interest) vs $469/month over 72 months ($5,788 in interest).
Is it better to finance through the dealer or my bank?
Get pre-approved from your bank or credit union before visiting the dealer. This gives you a baseline rate to compare against the dealer's offer. Dealers sometimes offer promotional rates (like 0% APR) on new cars that beat bank rates. However, dealer financing on used cars often has higher rates. Having a pre-approval also gives you negotiating leverage.
How does a trade-in affect my car payment?
A trade-in reduces the amount you need to finance, lowering your monthly payment. For example, trading in a car worth $8,000 on a $35,000 vehicle means you only finance $27,000 (minus any additional down payment). However, make sure you negotiate the trade-in value and new car price separately to get the best deal on both.
What is the true cost of owning a car?
The true cost goes far beyond the monthly payment. You need to account for: auto insurance ($1,200-$2,400/year), maintenance and repairs ($500-$1,200/year), fuel ($1,500-$3,000/year), registration and taxes, depreciation (new cars lose 20-30% of value in the first year), and potential parking costs. The total cost of ownership can be 50-100% more than just the loan payments.

Related Calculators