How it works
The target percentage is applied to the vehicle price before any financed fees. If your trade-in is worth more than you owe on it, that positive equity counts toward the target. If you owe more than it's worth, the shortfall raises the cash you need to reach the same net contribution. Enter the full trade allowance and the loan payoff separately so the debt stays visible.
The tool compares the cash you'd need with what's left of your savings after the reserve you choose to keep. It then estimates a loan as if you paid the target down payment, even when there's a funding gap. So the loan figure shows what the loan would look like once the target is funded; it doesn't prove you have the money or that a lender will approve it. Every tax and fee you enter is treated as financed, so anything you'll pay in cash needs its own line in your budget.
The formula behind the estimate
Every result starts with a defined model and visible assumptions.
Target net contribution = vehicle price × selected percentage ÷ 100 Trade equity = trade allowance − existing loan payoff Cash needed = max(0, target net contribution − trade equity) Cash available = max(0, savings − reserve) Funding gap = max(0, cash needed − cash available) Amount financed = max(0, price + financed fees + payoff − trade allowance − cash down)
A worked example
Take a 20,000 car and a 20% target, so you aim to put 4,000 in. A trade allowance of 8,000 with a 5,000 payoff gives 3,000 of equity, which leaves 1,000 in cash. With 1,500 of financed fees, the loan comes to 17,500. If you have 6,000 saved and want to keep 2,000, then 4,000 is available and there's no funding gap. The amounts are examples only.
Is there a right down payment percentage?
Not one that works for everyone. The comparison table shows 10%, 20% and 30% so you can see how the same trade and fees change your cash needs and your loan. None of them is a lender requirement or a guarantee of affordability. A bigger down payment means less borrowing when everything else is equal, but it can leave you short for repairs, insurance or ordinary bills.
How do cash and trade equity fit together?
If your equity alone covers the target, the cash needed is zero. Equity beyond the purchase total can leave credit that has to be settled with the seller. Negative equity is debt, and this model asks for enough extra cash to cover it before reaching your target. If you'd rather roll that shortfall into the new loan, the car loan calculator shows what that does to the payment.
What about local prices and currency?
Changing the currency only changes labels and formatting. It doesn't convert numbers or apply a tax rate, so use the same currency for savings, price, trade allowance and payoff. Fees, lender rules and contract types differ from country to country; enter charges you've verified, and use a conventional monthly loan rate for the payment illustration.
Questions worth asking
Is 20% down required to buy a car?
No. Twenty percent is a common comparison target, not a rule. What you actually need depends on the lender's requirements and how much cash your household can spare.
Can a trade-in cover my down payment?
Yes, if you have positive equity. Subtract the loan payoff from the agreed trade allowance; the full allowance isn't spendable equity if you still owe money on the car.
What happens with negative equity on a trade?
This model increases the cash you need by the shortfall. If you'd rather finance the shortfall, the car loan calculator can show how that changes your payment and interest.
Does a payment result mean I can afford the target?
Not by itself. Look at the funding gap and your reserve first. The loan figure assumes the target cash is paid and doesn't check your income or a lender's approval.
Are taxes calculated automatically?
No. Enter the taxes and fees you've verified for your location and mark only the financed ones. Amounts you pay upfront need extra cash outside this model.
This is general information, not personalized financial advice. Read the limitations.
