This page is a US-style car note. Enter cash price, down payment, APR, and term in months. The amount financed is price minus down. The result is a monthly payment from the same amortizing formula as the mortgage tool, plus total paid and total interest. It is not a dealer pencil and it is not an approval.
A worked case from the tests: $30,000 financed at 7% for 60 months. Monthly payment is about $594. Change the down payment and you change P, not the rate. Change the term and you change n — a 72-month note looks cheaper per month and costs more interest if you keep it.
A second case from this engine: $25,000 financed at 7.5% for 60 months is $500.95 a month. Total paid is $30,057.00. Interest is $5,057.00. Stretch the same $25,000 to 72 months at the same 7.5%: $432.25 a month, $31,122.00 total, $6,122.00 interest. The longer note is $68.70 cheaper each month and $1,065.00 more expensive if you keep it. That $68.70 is what people buy when they “need the payment to fit.” Insurance and fuel still sit outside both numbers.
What belongs in the amount financed
Sales tax, title, and documentation fees belong in the payment only if they are in the number you finance. Many US dealers roll tax into the note. If you pay tax in cash at the window, do not add it to price here or you will double-count. Extended warranties and GAP are the same rule: in the loan, or not.
Zero down and a long term can hide a payment that still fits a budget while the car is worth less than the note in year one. That gap is negative equity. This calculator will not stop you. It will only show the monthly number. Trade-in equity belongs in down payment only if the dealer actually applies it that way on the buyer’s order.
Rate vs term
Credit-union and bank APRs differ from dealer-arranged paper. A lower rate on a shorter term can beat a “low payment” 84-month offer. Run the page twice and subtract total interest. That difference is the price of the longer note, before insurance and fuel. Used-car APRs are often higher than new-car APRs on the same bureau file; the formula does not know the vehicle year, only P, r, and n.
We do not originate auto loans. There is no application and no soft pull. Your dealer or credit-union quote wins. Ads load only after a result. If you are checking whether the payment fits a paycheck, open the paycheck tool with the same household and subtract this monthly number from take-home before you sign. The 60 vs 72 guide walks the $25,000 case in full.