Motor Loan Calculator
Price a motor loan before you sign. Enter the vehicle price, down payment, trade-in, APR and term to get your monthly payment, total interest and total cost. Compare every common term side by side, see the yearly amortization, check affordability against your income, and test what an extra monthly payment saves.
Monthly payment
The affordability verdict uses a flat 15% of the monthly income you enter: it compares the payment alone, not payment plus insurance and fuel. Results are estimates; your lender’s exact APR, fees and rounding may differ slightly.
Quick Answer
A $30,000 vehicle with $5,000 down at 7% APR for 60 months finances $25,000 and costs $495.03/month, with $4,702 total interest and $29,702 total of payments. Stretching the same loan to 84 months drops the payment to $377.32 but raises total interest to $6,695. The calculator above is pre-filled with this exact example.
Key takeaways
- The amount financed is price minus down payment minus trade-in plus any tax and fees you roll in. Every dollar there changes both the payment and the interest.
- Term length is the biggest lever you control: 84 months saves about $118 a month versus 60 months on the example but costs about $1,993 more in interest.
- An extra $100 a month on the example ends the loan in 49 months instead of 60 and saves $939 in interest.
- The 15% check compares the payment against your monthly income. At $5,000/month income, the $495.03 payment is 9.9%, comfortably inside.
How to use the motor loan calculator
Enter the deal numbers, pick a term, and click Calculate. Results stay hidden until you click. The tool is pre-filled with the worked example so you can press Calculate immediately and see every output.
- Vehicle price: the agreed sale price before tax and fees.
- Down payment and trade-in: both reduce the amount financed dollar for dollar. The classic target is 20% down on a new car, which roughly offsets the first year of depreciation.
- Sales tax and fees: optional. Rolling them in raises the principal and the interest; paying them in cash keeps the loan smaller. The CFPB notes which costs are negotiable and which, like government taxes and title fees, are not.
- APR and term: enter the annual rate and choose 36 to 84 months. Experian’s Q2 2026 data puts the average new-car rate at 6.35% and the average used-car rate at 11.19%, so a 7% example sits squarely in the real market.
- Extra payment and income: optional. The extra-payment box runs a full payoff simulation; the income box runs the 15% affordability check.
Blank optional boxes (trade-in, tax and fees, extra payment) count as zero. Only the vehicle price and APR are required. If the down payment and trade-in cover the whole price, the tool says so instead of calculating a loan on nothing.
The motor loan formula
The monthly payment comes from the standard amortization formula: payment equals the principal times the monthly rate times (1 plus the monthly rate) to the power of the number of months, divided by ((1 plus the monthly rate) to the power of the number of months minus 1).
Monthly rate = APR ÷ 12
Payment = Principal × r(1+r)^n ÷ ((1+r)^n − 1)
Total interest = Payment × Months − Principal
Early payments are mostly interest; each month the interest portion shrinks and the principal portion grows. That is exactly what the yearly amortization table below the results shows: in year one of the example, roughly $1,616 of the $5,940 paid is interest, while in the final year interest is only about $218. The math is the same annuity formula lenders use under the Truth in Lending Act to disclose payments. For a month-by-month view of any loan, the amortization schedule calculator breaks every payment into principal and interest.
Worked example, checked against this exact tool
The pre-filled run is a $30,000 vehicle, $5,000 down, no trade-in, no financed fees, 7% APR, 60 months. Every row below is a verified run of the calculator above.
| Run | Monthly payment | Total interest | Extra result |
|---|---|---|---|
| Worked example: $30k, $5k down, 7%, 60 mo | $495.03 | $4,702 | 9.9% of $5,000 income: affordable |
| With $100/mo extra payment | $495.03 + $100 | $3,763 | Paid off in 49 mo, $939 saved |
| Trade-in $2,000, $4,000 down + $1,800 tax and fees, 6.5%, 48 mo | $493.27 | $2,877 | Financed $20,800 on a $25,000 price |
| Zero-interest loan: $20,000, 0% APR, 36 mo | $555.56 | $0 | Payment is just principal ÷ months |
The step-by-step line under the results shows the same arithmetic in plain numbers: $30,000 − $5,000 − $0 + $0 = $25,000 financed; monthly rate 7% ÷ 12 = 0.5833%; payment $495.03; total interest $495.03 × 60 − $25,000 = $4,702.
Short term vs long term
Stretching the term cuts the monthly payment but raises total interest and slows equity buildup. The table below prices the worked example ($25,000 financed at 7%) across every common term; the calculator’s own term-comparison table does the same for your numbers with your chosen term starred.
Two warnings travel with long terms. First, the interest cost: 84 months saves about $118 a month versus 60 months but costs about $1,993 more in interest. Second, negative equity: the calculator warns on any term of 72 months or more because a car can lose 20 to 30% of its value in two years, so with little down you can owe more than the car is worth for years. Experian’s Q2 2026 figures show the average new-car loan term at 69.5 months, which is exactly why the warning matters for most buyers. If you are already in a long loan, the auto loan principal payment calculator models extra payments against your remaining balance.
The 15% affordability guideline
A common guideline caps the monthly vehicle payment near 15% of monthly take-home pay. Enter your income and the tool shows a verdict: payments at or under 15% get an “Affordable” badge, anything above gets an “Above the 15% guideline” flag.
Be honest about what the tool checks: it compares the payment alone against the income you enter, not payment plus insurance and fuel. A fuller budget check adds those costs, which is why the 20/4/10 rule uses 10% of gross income for the whole car. Insurance alone can move the needle: the car insurance cost per month calculator estimates that slice before you add it to the payment. Your debt-to-income ratio is the lender’s version of the same question, and the debt-to-income ratio calculator runs that check properly.
What competing calculators miss
Most auto-loan tools cover the payment and stop. Here is what the established pages each leave out, and what this page adds:
- PrimeCalculator’s auto loan tool: term comparison table, trade-in and tax handling, and a yearly amortization schedule, which is genuinely good. What it does not do: no affordability check against income, and no extra-payment payoff simulation. This page has both.
- Ally’s 2026 auto loan calculator: clean term comparison with a highlighted row and rate-tier guidance tied to its 5.69% starting APR. It is built around Ally’s own product and does not model trade-in, tax, fees, or extra payments.
- Honda/FinzByte’s car loan calculator: the only competitor with a real affordability verdict, using 10-15% of take-home as “healthy” and 15-20% as “stretch”. This page’s 15% line matches the conservative end of that scale, and unlike theirs it also runs the extra-payment and term-comparison math in the same tool.
- CalcWorker’s auto loan page: strong on the strategic guidelines (20% down, 48-month cap, months-underwater estimates per term). But it is a table of static numbers, not a calculator: you cannot enter your own deal. This page lets you run your own numbers and get the same strategic framing.
- Softonic’s auto loan calculator: a good term table (36 to 84 months) and a clear five-step how-to. No income check, no extra-payment math, no tax and fee inputs.
- LoanCalc.tech’s EMI calculator: honest about credit tiers and used-car rate premiums, but its tool takes only loan amount, rate and term. No down payment, trade-in, tax, fees, affordability, or extra-payment handling.
- The gap this page fills: one tool that takes the full deal (price, down, trade-in, tax and fees), compares every common term with your term starred, shows yearly amortization, checks affordability against your income, simulates extra payments, and warns about negative equity on 72-plus-month terms.
Frequently asked questions
Payment = principal × r(1+r)^n ÷ ((1+r)^n − 1), where the principal is price minus down payment minus trade-in plus any financed tax and fees, r is APR ÷ 12, and n is months. A $25,000 loan at 7% APR for 60 months is $495.03/month.
Monthly payment × months minus the principal. The worked example pays about $4,702 in interest over 60 months; the same loan over 84 months pays $6,695. The calculator’s term table shows the interest for every common term.
Not automatically, but it costs more interest and creates negative-equity risk: the car’s value can fall faster than the balance, so you can owe more than it is worth for years. The calculator shows an explicit warning on any term of 72 months or more.
20% on a new vehicle is the classic target: it offsets first-year depreciation and keeps you above water from day one. On a used vehicle, where depreciation is gentler, 10% is a common minimum.
It goes straight to principal, shortening the loan and cutting interest. An extra $100/month on the worked example ends the loan in 49 months instead of 60 and saves $939 in interest. Enter your own extra amount to see your payoff date and savings.
It depends on credit score and term. Experian’s Q2 2026 data shows average new-car APRs from 4.41% for super-prime borrowers (781-850) to 16.11% for deep subprime, and 6.29% to 21.62% on used cars. Get pre-approved by a bank or credit union before the dealership so you have a rate to beat.
Financing them raises the principal and the interest paid. Paying them in cash keeps the loan smaller. The tool lets you model either: enter the tax and fees in the optional box, or leave it blank to pay them outside the loan.
Keep the payment near 15% of your monthly take-home pay. Enter your income and the calculator flags payments above that line. For the full picture, add insurance and fuel to the payment, or run your total debts through the debt-to-income ratio calculator.
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References
- Consumer Financial Protection Bureau. Auto loans: steps for getting an auto loan. Accessed October 23, 2026.
- Consumer Financial Protection Bureau. Ask CFPB: What things can I negotiate when shopping for a car or auto loan? Accessed October 23, 2026.
- Consumer Financial Protection Bureau. Ask CFPB: How will shopping for an auto loan affect my credit? Accessed October 23, 2026.
- Federal Reserve Board. Consumer Credit G.19: terms of credit at commercial banks and finance companies. Accessed October 23, 2026.
- Experian. Average car payment in 2026: interest rates by credit score. Accessed October 23, 2026.
- Experian. What is a good credit score for an auto loan? Accessed October 23, 2026.
- Experian. Auto loan rates and financing for 2026. Accessed October 23, 2026.
- Experian. What is the average length of a car loan? Accessed October 23, 2026.
- Experian. The latest used car loan interest rates for 2026. Accessed October 23, 2026.
- Bankrate. Auto loan rates and financing in 2026. Accessed October 23, 2026.