Car Payment Calculator
Use our free online Car Payment Calculator to perform fast, accurate calculations with instant formulas, step-by-step arithmetic, and verified reference benchmarks.
Auto Loan & Car Payment Calculator
How to Calculate: The Car Payment Calculator Formula
Where P is the financed vehicle balance (Purchase Price - Down Payment - Trade-in Credit + Sales Tax), r is the monthly interest rate, and n is the loan term in months.
Step-by-Step Calculation Guide
- Enter the vehicle negotiated purchase price.
- Specify cash down payment and trade-in value allowance.
- Input local state/county vehicle sales tax rate (percentage).
- Select loan duration (36, 48, 60, or 72 months) and loan APR interest rate.
- Review total monthly car note, total finance charges, and overall vehicle investment.
Practical Car Payment Calculator Examples
Vehicle Price: $35,000, Down Payment: $5,000, Trade-in: $3,000, Sales Tax: 7%, APR: 6.5%.
Vehicle Price: $18,000, Down Payment: $2,000, Sales Tax: 6%, APR: 8.0%.
Loan Term Comparison for $30,000 Auto Loan at 7.0% Interest
Official reference values and benchmark classifications based on standard institutional guidelines.
| Loan Duration | Monthly Car Payment | Total Interest Cost | Total Cost of Vehicle |
|---|---|---|---|
| 36 Months (3 Yrs) | $926.34 | $3,348.24 | $33,348.24 |
| 48 Months (4 Yrs) | $718.39 | $4,482.72 | $34,482.72 |
| 60 Months (5 Yrs) | $594.04 | $5,642.40 | $35,642.40 |
| 72 Months (6 Yrs) | $511.66 | $6,839.52 | $36,839.52 |
Frequently Asked Questions about Car Payment Calculator
What is the 20/4/10 rule in car buying?
The 20/4/10 rule recommends putting down at least 20% cash, financing for no more than 4 years (48 months), and keeping total vehicle expenses (payment, insurance, fuel) under 10% of gross monthly income.
How does loan length affect your monthly payment and interest?
Longer terms (e.g. 72 or 84 months) lower your monthly payment but significantly increase total interest paid and increase the risk of negative equity (being "underwater").
Does vehicle trade-in reduce sales tax?
In most US states, trade-in value is subtracted from the purchase price before sales tax is assessed, saving you money on taxes.
What credit score is needed for best auto loan interest rates?
Super-prime auto rates are typically reserved for credit scores of 740 and higher, while scores below 620 face subprime rates of 12% to 20%+.