Down Payment Calculator

Choose percent or fixed down payment. Optionally add tax/fees and apply trade-in, rebate, and payoff to estimate your amount financed.

How to Use

  1. Enter the purchase price (or home price).
  2. Select down payment mode: percent or fixed amount.
  3. (Optional) Add sales tax and fees, then add trade-in/rebate/payoff if relevant.
  4. Open “Show Work” for the exact steps and formulas used.
Down Payment
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Amount Financed
—
Estimated principal after credits
Out-the-Door Total
—
Price + tax + fees
Credits Applied
—
Down + trade + rebate
Inputs

All math runs locally in your browser. Nothing is uploaded.

Vehicle/home price before tax/fees (USD).
Percent is based on purchase price.
Typical: 3–20% depending on loan type.
Optional: Tax, Fees, Trade-in, Rebate, Payoff
If blank, tax is treated as $0.
Doc, title, registration, delivery, etc.
Credit applied to the deal.
Manufacturer incentives, promotions, etc.
If you owe money on the trade-in, this increases financed amount.
Some areas tax fees; this lets you model both.
Assumption: Trade-in and rebates are treated as credits (reduce amount financed). Payoff is treated as added cost (increases amount financed).
Show Work (step-by-step)
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Work is shown in USD with straightforward rounding for display. Internal math keeps full precision.

Reference

  • Down (percent): down = price × (percent / 100)
  • Out-the-door: otd = price + tax + fees
  • Credits: credits = down + tradeIn + rebate
  • Amount financed (estimate): financed = max(0, otd - credits + payoff)

This calculator estimates principal (amount financed). Your lender contract may handle tax and credits differently by location and program.

FAQ

Is a bigger down payment always better?

Usually it lowers amount financed and payment, but you may prefer keeping cash on hand. The “best” depends on rate, loan term, and your budget.

Does trade-in reduce taxes?

In some areas, trade-in reduces the taxable amount. This tool keeps tax simple and separate; use your local rules for final numbers.

What if credits exceed the out-the-door total?

This tool floors “amount financed” at $0. Any excess credit would typically be handled as cash back or applied differently depending on the deal.

Tool Info

Last updated:

Updates may include additional local tax logic options and improved edge-case handling.