Last updated: May 2026
Enter your vehicle price, down payment, trade-in, and loan details to calculate your exact monthly payment and total interest.
Vehicle Details
Loan Terms
Amortization Summary
Formula: Monthly Payment = P × [r(1+r)^n] / [(1+r)^n − 1]
Where P = loan principal (price − down payment − trade-in + tax), r = monthly interest rate (APR ÷ 12), n = number of months.
Each month: Interest portion = remaining balance × monthly rate. Principal portion = monthly payment − interest. Balance decreases by the principal portion each month.
Rate & Term Reference — $30,000 Loan
Monthly payment at different rates and terms (principal only, no taxes/fees).
⚠️ Results are estimates based on a simple interest amortization model. Actual loan terms may include fees, dealer add-ons, or differing compounding schedules. Consult your lender for exact figures.
Related Calculators
Auto loans use the same standard amortization formula as mortgages and personal loans. Your monthly payment is fixed; early payments are mostly interest, later payments mostly principal.
Where P is the amount financed (purchase price minus down payment minus trade-in value), r is the monthly interest rate (APR / 12), and n is the loan term in months.
Worked example: $35,000 car, $5,000 down, $30,000 financed at 7.5% APR for 60 months: Monthly payment = $601. Total interest = $601 x 60 - $30,000 = $6,060. Extending to 72 months saves $80/month but adds $1,400 in total interest. The general guideline: no more than 15% of take-home pay on all vehicle costs (payment + insurance + fuel + maintenance).
Auto loan rates vary significantly by credit score and whether the car is new or used. As of 2026, new car loan averages: Excellent credit (750+): 5-6.5% APR. Good credit (700-749): 6.5-9% APR. Fair credit (650-699): 9-15% APR. Used car loans run 1-3% higher than new car rates at the same credit tier. Credit union and manufacturer financing often beat bank rates — compare at least three offers before accepting dealer financing.
A larger down payment reduces your principal, monthly payment, and total interest. It also protects against being underwater (owing more than the car is worth) — cars depreciate roughly 15-25% in the first year and 50-60% in five years. A 20% down payment on a new car roughly matches first-year depreciation, keeping you above water. If your interest rate is very low (under 4%), investing the down payment difference may return more than the interest saved.
The auto industry's shift to 72- and 84-month loans has made cars seem more "affordable" while dramatically increasing total interest cost. A $30,000 loan at 7.5% APR: 48 months = $726/mo, $4,832 interest. 60 months = $601/mo, $6,060 interest. 72 months = $516/mo, $7,152 interest. 84 months = $455/mo, $8,220 interest. The 84-month loan has 70% more total interest than the 48-month loan while making the car look only $270/month cheaper.
GAP (Guaranteed Asset Protection) insurance pays the difference between what your car is worth and what you owe on the loan if the car is totaled or stolen. It is most valuable when you financed with a small down payment, have a long loan term, or bought a fast-depreciating vehicle. GAP insurance from a dealer typically costs $400-$900 added to the loan; through your auto insurer it costs $20-$40/year. Always buy through your insurer if you need it — dealer pricing is inflated.
A 10% down payment is the baseline — it reduces your loan amount and limits early negative equity as the car depreciates. The rates below reflect 2025 averages for buyers with good credit (700+). Buyers with excellent credit (750+) can often find rates 1–1.5% lower, especially through credit unions or manufacturer incentive financing.
Keep in mind that the payment shown is only part of the true cost of ownership. Add insurance, fuel, maintenance, and registration to get an accurate monthly vehicle budget. The general rule of thumb: total vehicle costs should not exceed 15% of your monthly take-home pay.
| Vehicle Price | Down Payment | Rate (60mo) | Monthly Payment | Total Interest |
|---|---|---|---|---|
| $25,000 | $2,500 | 5.5% | $425 | $2,990 |
| $35,000 | $3,500 | 6.0% | $609 | $4,528 |
| $45,000 | $4,500 | 6.5% | $792 | $6,104 |
| $55,000 | $5,500 | 7.0% | $977 | $7,762 |
| $65,000 | $6,500 | 7.5% | $1,168 | $9,613 |
What is a good interest rate for a car loan?
For new cars in 2025–2026, a good rate is below 6% APR for buyers with excellent credit (750+) and below 8% APR for good credit (700–749). Used car loans typically run 1–3% higher than new car rates at the same credit tier due to higher lender risk. Credit unions consistently offer rates 1–2% below banks and dealers. Always get pre-approved by a credit union or bank before visiting the dealership — dealer financing is convenient but rarely the cheapest option.
Should I finance through the dealer or my bank?
Get pre-approved by your bank or credit union before going to the dealership. This gives you a competitive benchmark and negotiating power. Dealers act as intermediaries for lenders and often mark up the interest rate (called "dealer reserve") by 0.5–2.5%, keeping the difference as profit. Sometimes manufacturers offer below-market promotional rates (0–3.9% APR) on specific models — compare these against your pre-approval. If the promotional rate is lower, take it; otherwise use your own financing.
How much car can I afford?
A common guideline is the 20/4/10 rule: put at least 20% down, finance for no longer than 4 years, and keep total vehicle expenses (payment + insurance) at or below 10% of gross monthly income. A stricter but safer benchmark is 15% of take-home (after-tax) pay for all vehicle costs including fuel and maintenance. On a $5,000/month take-home salary, that's $750/month total — leaving roughly $450–500 for a car payment after insurance and fuel.
What is a good down payment on a car?
The traditional recommendation is 20% down on a new car and 10% on a used car. A 20% down payment on a new vehicle roughly covers first-year depreciation, keeping you from going underwater on the loan immediately. Putting less down increases your monthly payment, total interest, and risk of negative equity. If you can't put 20% down on a new car, consider a less expensive model, a certified pre-owned vehicle, or delaying the purchase until you've saved more.
Does loan term affect my interest rate?
Yes. Longer loan terms (72–84 months) typically carry higher interest rates than shorter terms (36–48 months) because lenders face more risk over a longer period with a depreciating asset. The combination of a higher rate and more months of interest compounding means 84-month loans can cost 60–80% more in total interest than 48-month loans on the same purchase price. The auto industry promotes longer terms because they make expensive vehicles appear more affordable on a monthly basis.