Auto Loan Calculator

Buying a car is one of the largest financial commitments most people make outside of purchasing a home.

Reviewed by: CalcMojo Editorial Team

Our auto loan calculator helps you estimate your monthly car payment before you ever step foot in a dealership, giving you the confidence to negotiate from a position of knowledge rather than guesswork.

Enter your vehicle price, down payment, trade-in value, loan term, and interest rate to get an instant breakdown of your monthly obligation. The auto loan calculator also factors in sales tax so you can see the true financed amount rather than just the sticker price. Whether you are purchasing a brand-new sedan or a certified pre-owned truck, understanding your payment ahead of time prevents you from stretching your budget past its limits.

Use this tool to compare different scenarios side by side. See how a larger down payment shrinks your monthly bill, how trading in your current vehicle reduces the loan principal, or how choosing a shorter term saves you thousands in interest over the life of the loan. Adjusting even one variable can reveal surprising differences in total cost, making this calculator an essential step in the car-buying process.

How Auto Loan Payments Are Calculated

Every auto loan payment is determined by three core variables: the amount you finance, the annual interest rate, and the number of months in your repayment term. Lenders use the standard amortization formula (often referred to as the PMT formula) to convert these inputs into a fixed monthly payment that covers both principal and interest over the life of the loan.

The formula works by distributing the total interest cost evenly across every payment so that each installment is identical. In the early months, a larger share of your payment goes toward interest. As the loan matures, the balance shifts and more of each payment chips away at the principal. This is why paying extra in the first year or two of a loan can have a dramatic effect on the total interest you pay — early principal reductions shrink the base on which future interest is calculated.

Your financed amount is not simply the vehicle price. It equals the purchase price minus your down payment, minus the value of any trade-in, plus applicable sales tax on the net amount. Some states tax the full purchase price, while others tax only the difference after a trade-in deduction. The calculator lets you model both approaches so you can match the rules in your jurisdiction.

New vs Used Car Loan Rates

Interest rates on auto loans vary significantly depending on whether the vehicle is new or used. New car loans typically carry lower rates because the collateral — the car itself — holds its value more predictably over the loan term. Lenders face less risk when financing a vehicle that comes with a full manufacturer warranty and a known maintenance history of zero.

Used car rates tend to be higher, often by one to two percentage points or more. The older the vehicle and the higher the mileage, the greater the risk that it will depreciate below the remaining loan balance, leaving the lender with insufficient collateral in the event of a default. Certified pre-owned vehicles sometimes qualify for rates that fall between new and standard used tiers because they come with extended warranties and have passed multi-point inspections.

Credit unions and direct lenders frequently offer more competitive used-car rates than dealership financing desks. Before you visit a lot, get pre-approved through your bank or credit union so you have a benchmark rate. You can then let the dealer try to beat it, which often results in a lower offer than you would have received by accepting their first quote.

How Car Loan Interest Works

Auto loans use simple interest calculated on a daily basis against the outstanding principal balance. Each day, the lender multiplies your remaining balance by the daily interest rate (your annual rate divided by 365). When your monthly payment arrives, the accrued interest is paid first, and the remainder reduces the principal.

This structure means that the timing of your payments matters. If you make a payment a few days early, slightly less interest has accrued, so a marginally larger portion of that payment goes toward principal. Over a five- or six-year loan, consistently paying a day or two early can shave a small but meaningful amount off your total interest cost.

Beware of loans that front-load interest through precomputed interest structures. These are less common today but still exist at some buy-here-pay-here lots. With precomputed interest, paying early does not reduce your total cost because the interest was baked into the loan balance from day one. Always confirm that your loan uses simple interest before signing.

Choosing the Best Loan Term (24-84 Months)

The length of your loan term is one of the most consequential decisions in the car-buying process. Shorter terms mean higher monthly payments but dramatically lower total interest costs. Longer terms make each payment more affordable but increase the cumulative price you pay for the vehicle.

A 24-month loan is the most aggressive repayment schedule commonly offered. Monthly payments will be high, but you will pay the least interest of any term and build equity in the vehicle almost immediately. This option works well for buyers who can comfortably absorb the larger payment without straining their monthly budget.

A 36-month loan offers a middle ground for disciplined buyers. Payments are still substantial, but the total interest cost remains low, and you will own the car free and clear in just three years. This term is popular among buyers who plan to keep their vehicle for a long time and want to minimize financing costs.

A 48-month term has traditionally been the standard auto loan length. It balances affordability with reasonable total cost. Most buyers who choose this term are financing a moderately priced vehicle and want a payment that fits comfortably within their monthly budget without dragging the loan out for half a decade.

A 60-month loan is now one of the most common terms in the market. It lowers the monthly payment further, but interest accumulates meaningfully over five years. Buyers should be aware that depreciation may outpace equity buildup during the first two or three years, creating a period where you owe more than the car is worth.

A 72-month loan pushes into territory where caution is warranted. Six years is a long time to carry a car payment, and the vehicle will lose a significant portion of its value during that window. If you need to sell or trade in the car before the loan is paid off, you may find yourself underwater, meaning you owe more than the vehicle is worth and must bring cash to the table to close the deal.

An 84-month loan maximizes affordability on a per-month basis but comes with the highest total interest cost and the greatest risk of negative equity. Financial advisors generally recommend this term only for buyers who are financing a vehicle they intend to keep for the entire loan period and well beyond. If you find that you need an 84-month term to afford the monthly payment, it may be a signal that the vehicle is more expensive than your budget supports.

As a rule of thumb, aim for the shortest term you can comfortably afford. Every month you shave off the loan reduces the total interest paid. Use the calculator above to compare a 48-month term against a 72-month term on the same vehicle — the difference in total cost is often enough to fund a significant repair or cover several months of insurance premiums.

Total Cost of Vehicle Ownership

Your monthly loan payment is only one component of the true cost of owning a car. A complete picture includes insurance premiums, fuel or charging costs, routine maintenance, registration and inspection fees, and depreciation. Failing to account for these expenses is one of the most common budgeting mistakes new car buyers make.

Insurance costs vary widely based on the vehicle model, your driving record, your location, and your coverage levels. A sports car with a high theft rate will cost substantially more to insure than a mid-size sedan with top safety ratings. Get insurance quotes before you commit to a purchase so you know the full monthly obligation.

Fuel costs depend on the vehicle’s efficiency and your driving habits. A commuter who drives 15,000 miles per year in a vehicle that gets 25 miles per gallon at $3.50 per gallon will spend roughly $2,100 annually on fuel alone. Use our Fuel Cost Calculator to model your specific scenario.

Maintenance and repair costs rise as the vehicle ages. New cars under warranty have minimal out-of-pocket maintenance costs, but once the warranty expires, you become responsible for everything from brake pads to transmission service. Budget at least one to two percent of the vehicle’s value per year for maintenance, and more for older or higher-mileage vehicles.

Depreciation is the silent cost that many buyers overlook. A new car loses roughly 20 percent of its value in the first year and continues to depreciate at a declining rate for several years after that. Buying a vehicle that is two or three years old lets someone else absorb the steepest part of the depreciation curve while you enjoy a car that is still relatively new.

Tips for Getting the Best Auto Loan Rate

Your credit score is the single largest factor determining the interest rate you qualify for. Before you begin shopping for a vehicle, check your credit report for errors and take steps to improve your score if it is below 700. Even a modest improvement can shift you into a lower rate tier and save hundreds or thousands of dollars over the life of the loan.

Shop multiple lenders. Rates vary between banks, credit unions, online lenders, and dealership finance offices. Applying to several lenders within a short window (typically 14 to 45 days depending on the scoring model) counts as a single inquiry on your credit report, so there is no penalty for comparison shopping.

Make a meaningful down payment. Putting at least 10 to 20 percent down reduces the amount you finance, lowers your monthly payment, and signals to lenders that you have skin in the game. Buyers who put nothing down are statistically more likely to default, which is why zero-down loans often carry higher rates.

Consider a shorter loan term. Lenders typically offer lower rates on shorter terms because the risk of default and collateral depreciation is reduced. A 48-month loan almost always carries a lower rate than a 72-month loan on the same vehicle, compounding the savings you get from the shorter repayment period.

Avoid add-ons that inflate the loan balance. Extended warranties, gap insurance, paint protection packages, and other dealer-offered products increase the amount you finance and the interest you pay. If you want these products, price them independently and pay for them out of pocket rather than rolling them into the loan.

Use our Loan Calculator for general loan comparisons, our Compound Interest Calculator to understand how interest compounds on different financial products, and our Fuel Cost Calculator to estimate ongoing vehicle operating costs.

This calculator provides estimates for informational purposes only. It is not financial advice. Results may not reflect your actual loan terms, tax situation, or investment returns. Consult a licensed financial advisor, CPA, or mortgage professional before making financial decisions.

Sources & Methodology

Auto loan payments calculated using the standard amortization formula (PMT). Sales tax applied to the financed amount after down payment and trade-in deductions.

Default rates shown are illustrative. Always verify current rates with your lender. Data accurate as of: March 2026