Auto Loan Calculator
Last updated July 2, 2026
Last reviewed July 8, 2026
An auto loan is typically the second-largest debt most people carry, and the monthly payment focus that drives most car purchases masks a total cost that is much larger than the purchase price suggests. A $35,000 vehicle financed over 72 months at 7 percent costs $552 per month, appears manageable against most household budgets, and generates $4,744 in total interest. But by the end of the loan, the buyer has paid $39,744 for a vehicle that, due to depreciation, may be worth $18,000 to $22,000 — a gap between what was paid and what was received that reflects both financing cost and the economic reality of automobile depreciation.
The 72-month and 84-month auto loans have become increasingly common as vehicle prices have risen, but they carry structural risks beyond the interest cost. A buyer who finances a $40,000 vehicle over 84 months is in negative equity — owing more on the car than it's worth — for potentially four or five years of the loan. If the car is totaled, stolen, or sold during that period, standard insurance or proceeds pay the vehicle's market value, not the remaining loan balance. GAP insurance covers that difference, but it adds to the total cost of ownership. Financial advisors generally recommend keeping auto loan terms at 48 to 60 months, making a down payment of at least 20 percent, and ensuring the total monthly payment (principal, interest, insurance, fuel, and maintenance) doesn't exceed 15 to 20 percent of take-home pay.
The auto loan calculation shows total paid over the life of the loan — monthly payment times the number of months — and compares it to the vehicle's purchase price. The difference is total interest plus any fees. The vehicle's estimated value at loan payoff, using depreciation data from Kelley Blue Book or Edmunds, adds the second half of the comparison. That comparison shows the true economics of the financing decision and often reveals why a shorter term or larger down payment is worth pursuing.