Calcs4All

APR 23 · 2026

Auto loan calculator

Estimate monthly car payment, financed amount, and total financing cost with taxes, trade-in credit, and fees.

What this calculator covers

Use this auto loan calculator to estimate the monthly payment on a financed vehicle after factoring in down payment, trade-in credit, sales tax, and financed fees.

The walkthrough keeps the financed amount visible so it is clear how much of the deal is actually being borrowed instead of hidden inside a dealer worksheet.

Because tax treatment, doc fees, and lender rules vary by state and product, treat this as a planning tool rather than a binding loan disclosure.

Frequently asked questions

How does trade-in value affect my loan amount?
Trade-in credit reduces the taxable vehicle price before sales tax is calculated, then the trade-in value is subtracted from the out-the-door price along with the down payment. A higher trade-in value directly lowers the amount you need to borrow.
Is sales tax always calculated on the price after the trade-in?
The calculator applies tax to the vehicle price minus the trade-in value, which is a common approach. Actual sales-tax treatment varies by state — some states tax the full vehicle price regardless of trade-in — so treat the tax figure here as an estimate.
What counts as a financed fee?
Financed fees are dealer or lender charges rolled into the loan rather than paid as cash at signing, such as documentation fees or extended-warranty costs added to the principal. Entering them here shows their effect on monthly payment and total interest.
Why does total vehicle cost include my down payment?
Total vehicle cost adds together everything you pay — down payment, trade-in value credited, loan payments — to show the full cash outlay for the vehicle over the life of the loan, not just the borrowed portion.

Tool

Run the calculation

$
$
$
%
mo
%
$

RESULT · MONTHLY PAYMENT

â„–085

Primary result

$536.03

$32,000.00 with $4,500.00 down, $3,000.00 of trade-in credit, 6.5% sales tax, and 6.9% APR comes to about $536.03 per month, with $5,776.53 in financing cost.

Amount financed
$27,135.00
Sales tax
$1,885.00
Monthly payment
$536.03
Total interest
$5,026.53
Total cost of financing
$5,776.53
Total vehicle cost
$39,661.53

Step-by-step solution

  1. 1.Apply the simplified tax treatment to the vehicle price after trade-in credit, which puts $1,885.00 of tax on $29,000.00 of taxable value.
  2. 2.Subtract the down payment and trade-in credit, then add financed fees to reach an estimated amount financed of $27,135.00.
  3. 3.Use the fixed-rate amortization formula across 60 months to estimate $536.03 per month and $5,026.53 of interest.

Walkthrough

Visual walkthrough

Auto financing starts by figuring out what actually gets borrowed, then spreading that financed amount across a fixed payment schedule.

  1. 01

    Build the financed amount

    Vehicle price, simplified sales tax, and financed fees increase the subtotal, while the down payment and trade-in reduce what needs to be borrowed.

    $27,135.00 financed

  2. 02

    Set the fixed payment

    PMT = P × r / (1 - (1 + r)^-n)

    The financed balance, APR, and term months produce the scheduled monthly payment for a fully amortizing loan.

    $536.03 per month

  3. 03

    Read the financing cost

    Interest over the loan plus financed fees shows how much the borrowing structure adds on top of the vehicle itself.

    $5,776.53 financing cost