Down payment calculator
Enter the home price, your down payment percentage, the rate and term to see the cash needed, the loan amount, the monthly payment and whether PMI is likely.
Principal and interest only; excludes property tax, insurance, HOA and PMI amounts.
How this calculator works
The down payment is the part of the price you pay in cash; the rest is the mortgage. A larger down payment lowers both the loan and the monthly payment, and usually the interest rate.
In the US, a down payment below 20% typically means private mortgage insurance (PMI) until the loan balance falls to about 80% of the home value. PMI protects the lender, not you, and adds roughly 0.3-1.5% of the loan amount per year.
The formula
down payment = price × down-payment percentage
loan amount = price − down payment
monthly payment = loan × r ÷ (1 − (1 + r)^−n)
where r = annual rate ÷ 12 and n = years × 12A $400,000 home with 10% down: $40,000 cash, a $360,000 loan, and at 6.5% over 30 years a monthly principal-and-interest payment of $2,275.
Worked example
A 10 down payment on a 400,000 home is $40,000 in cash, leaving a $360,000 loan. At the rate and term entered the monthly principal and interest is $2,275.44. Mortgage insurance: Yes — under 20% down.
Common mistakes
- Spending all your cash on the down payment. Keep an emergency fund and closing costs (2-5% of the price) in reserve.
- Forgetting PMI. Under 20% down the monthly cost is higher than the payment alone.
- Ignoring property tax and insurance. Escrow payments often add hundreds a month on top of principal and interest.
Frequently asked questions
How much down payment do I need?
Conventional loans often allow 3-5%; FHA loans 3.5%; 20% avoids mortgage insurance and usually gets the best rate.
Can the down payment come from a gift?
Often yes, with a gift letter. Lenders require documentation of the source of funds.
Does a bigger down payment always make sense?
Not always: at low rates, keeping cash invested can beat the interest saved. It depends on your rate, risk tolerance and reserves.
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