Auto Loan Calculator

How to use this auto loan calculator

Start with the negotiated vehicle price — never the MSRP by default. Add your down payment and trade-in value, then your province's sales tax (GST/HST, plus PST or QST where it applies) and the dealer's documentation fee (these get financed too, which many buyers miss). Choose the APR from a pre-approval letter if you have one, and compare terms.

The math behind your car payment

The amount financed is: (price − trade-in) + sales tax on (price − trade-in) + fees − down payment. The monthly payment then follows the standard amortization formula:

M = P × [r(1 + r)ⁿ] ÷ [(1 + r)ⁿ − 1]

• M — monthly payment
• P — amount financed
• r — monthly interest rate (APR ÷ 12)
• n — loan term in months

Why the term matters more than the payment

Dealers negotiate on monthly payment because it hides cost. On a $30,000 financed amount at 7% APR: 36 months costs $3,340 in interest, 60 months costs $5,640, and 84 months costs $8,030 — nearly double the 36-month figure. Worse, cars depreciate fastest early, so long loans leave you owing more than the car is worth for years. If the payment only works at 72+ months, the honest answer is a cheaper car. Shopping for the loan itself? Our loan payment calculator lets you model extra payments to kill the loan early.

What this calculator doesn't include

Registration and title fees vary by state and aren't included (add them to the fees field if you know them). GAP insurance, extended warranties, and dealer add-ons are excluded — add their cost to the vehicle price if you plan to finance them. Insurance, fuel, and maintenance are ownership costs, not loan costs, but budget for them: they routinely exceed the loan payment itself.