Down Payment Calculator

The down payment calculator translates a percentage into home-buying dollars. Enter a purchase price and a down payment percentage, and it returns the cash down payment, remaining loan amount, and loan-to-value ratio. It is intentionally different from a mortgage payment tool: it does not estimate interest, taxes, insurance, or closing costs. Its job is to answer the first financing question clearly: how much cash goes into the purchase, and how much is still borrowed?

That simple split affects nearly every next step. A buyer comparing 5%, 10%, 15%, and 20% down can see how fast the loan amount changes. A seller credit or gift can be tested as a higher percentage. A savings goal can be converted into a realistic price range. Once you know the loan amount, estimate the principal-and-interest payment with the home loan calculator, add taxes and insurance with the PITI calculator, or test income limits with the home affordability calculator.

What the calculator includes

The form has two inputs: purchase price and down payment percentage. The purchase price is the agreed price or target price before financing. The down payment percentage is the share paid upfront. The calculator multiplies those two values to find the down payment amount, subtracts the result from the price to find the loan amount, and reports the loan-to-value ratio.

Loan-to-value, or LTV, is included because lenders use it to evaluate risk. A lower LTV means the buyer has more equity at closing. A higher LTV means the loan finances more of the property value. The output therefore connects a savings decision with underwriting language. For deeper LTV scenarios with second liens or an adjustable PMI threshold, use the LTV calculator. If LTV is above 80% and you are modeling a conventional loan, use the PMI calculator.

Formula

The down payment amount is:

$\text{down payment} = \text{purchase price} \times \frac{\text{down payment percent}}{100}$

The remaining loan amount is:

$\text{loan amount} = \text{purchase price} - \text{down payment}$

The loan-to-value ratio is:

$\text{LTV} = \frac{\text{loan amount}}{\text{purchase price}} \times 100$

The calculator rejects a purchase price of zero or less, rejects negative percentages, and rejects percentages above 100. It does not round the term or estimate an amortized payment because no interest rate or loan term is part of this calculation.

Worked example

Use the default inputs: a $425,000 purchase price and a 15% down payment. First convert the percentage to a decimal: 15% ÷ 100 = 0.15. Multiply the price by that decimal:

$425,000 × 0.15 = $63,750 down.

Next subtract the down payment from the purchase price:

$425,000 - $63,750 = $361,250 loan amount.

Finally divide the loan amount by the purchase price:

$361,250 ÷ $425,000 × 100 = 85% LTV.

Those values match the calculator result: the primary answer is $63,750, the remaining loan is $361,250, and the loan-to-value ratio is 85%. If you raise the down payment to 20% on the same price, the down payment becomes $85,000, the loan falls to $340,000, and LTV falls to 80%. That lower LTV can matter for mortgage insurance and pricing, but it also requires $21,250 more cash at closing before considering other costs.

How lenders use down payment and LTV

Lenders care about the down payment because it creates borrower equity and reduces the amount at risk. For many conventional mortgages, an LTV above 80% is commonly associated with private mortgage insurance. The CFPB describes PMI as insurance that protects the lender if the borrower stops making payments. PMI can make a lower down payment possible, but it adds cost and does not protect the borrower the way homeowners insurance does.

Down payment also interacts with debt-to-income. A larger down payment lowers the loan amount, which usually lowers principal and interest. That can help the housing payment fit a lender’s DTI limits. However, a buyer who drains savings may have weaker reserves, and reserves can matter in underwriting. Use the debt-to-income calculator to see payment pressure after you know the monthly amount.

Tips for choosing a down payment

Do not optimize only for the lowest loan amount. Keep enough cash for inspections, appraisal gaps, moving, initial repairs, utility deposits, furniture, and an emergency fund. Ask the lender how the interest rate, mortgage insurance, and fees change at different LTV levels. A jump from 10% to 15% down may help, but the biggest practical threshold could be 20%, or it could be another loan-program-specific point.

Separate the down payment from closing costs in your savings plan. CFPB Loan Estimate and Closing Disclosure forms show many costs outside the down payment, including prepaid items and escrow deposits. If a gift, grant, or seller credit is part of your plan, confirm documentation rules early. If the appraisal comes in lower than the contract price, your effective LTV may be based on the lower value, not simply the price you entered.

Informational note

This calculator is for planning and education. It is not a mortgage approval, closing-cost estimate, loan program eligibility decision, or advice to use all available cash. Verify program rules, PMI, grants, seller credits, and required reserves with your lender or housing counselor before committing to a purchase.

Sources

• CFPB Regulation Z, 12 CFR Part 1026 — current through 2026-07-09; APR, finance-charge, payment, disclosure and credit terminology; user-supplied illustrative loan formulas are not lender quotes.
• Calculation scope: The equations and assumptions described above are applied only to values entered in the form. No live rates, prices, tax rules, lender terms, or accounting classifications are fetched. Results are user scenarios, not quotes or prescribed classifications.