How to use the down payment calculator
- Enter the home price and your down payment, as a percent of the price or as a dollar amount.
- Enter the interest rate from a lender quote and choose the loan term.
- Open More options to set closing costs as a percent of the price, enter a mortgage insurance rate if you have a quote, and add your savings and monthly saving to see how long it takes.
- Read the loan amount, the monthly principal and interest and the cash needed at closing. The table compares the same home at 3%, 5%, 10%, 15%, 20% and 25% down, with your choice highlighted.
- Download the CSV or PDF of the comparison.
Formula
Down payment = home price x down payment percent
Loan amount = price - down payment
Payment = L x r / (1 - (1 + r)^-n), with r = APR / 12 and n = years x 12
Cash needed at closing = down payment + price x closing cost percent
Mortgage insurance, if you enter a rate = loan x yearly rate / 12, only when the down payment is under 20%
Months to save: each month, balance = balance x (1 + monthly rate) + deposit
The monthly savings rate is the equivalent of the APY you enter, so a 4% APY earns the same over a year as monthly compounding at a slightly lower rate. With no APY, the balance simply grows by the deposit each month.
Worked example: a $400,000 home
10% down: the down payment is $40,000.00, the loan is $360,000.00 and the loan-to-value ratio is 90%. At 6.5% for 30 years the payment is $2,275.44. With closing costs of 3% ($12,000.00), the cash needed at closing is $52,000.00.
Other levels, same home: 3% down is $12,000 and a $2,452.42 payment; 5% down is $20,000 and $2,401.86; 15% down is $60,000 and $2,149.03; 20% down is $80,000 and $2,022.62; 25% down is $100,000 and $1,896.20. Going from 10% to 20% down cuts the payment by $252.82.
Mortgage insurance, if quoted: at an example rate of 0.5% a year, the yearly cost on the 10% down loan is $360,000 x 0.5% = $1,800, or $150.00 a month. At 3% down it is $161.67 a month. At 20% down or more it is zero in this calculator.
Saving for it: with $12,000 saved and $1,500 added each month, the $52,000 goal takes 27 months. With 4% APY on the savings it takes 25 months.
How the down payment changes the loan
A bigger down payment shrinks the loan, which lowers the monthly payment and the total interest. It also lowers the loan-to-value ratio, the loan divided by the price. Lenders look at this ratio when pricing a loan, and a lower ratio often means more options. On the $400,000 example, every extra $20,000 down takes about $126 off the monthly payment at 6.5% over 30 years.
The 20% question and mortgage insurance
Lenders commonly charge mortgage insurance on conventional loans when the down payment is under 20% of the price, and the rules differ by loan program. This calculator shows an insurance line only if you enter a rate from a quote. It applies it when the down payment is below 20% of the price and drops it at 20%. How long insurance lasts, and how to end it, is set by your lender and loan type, so ask.
A smaller down payment can still be the right choice, especially if it lets you keep an emergency fund. The table lets you see the payment and the cash needed side by side for each level.
Cash needed beyond the down payment
Closing costs are paid in addition to the down payment, which is why the cash-to-close column is higher. Your Loan Estimate lists the real figures. Moving costs, repairs and a reserve for the first months in the home are also real needs and are not included here.
Next steps
Once you have a target, add tax, insurance and HOA dues in the mortgage calculator for a full monthly payment. To plan the saving period in more detail, use the savings calculator.
Assumptions and limits
- A fixed-rate loan with monthly payments. The payment shown is principal and interest only.
- Closing costs are the percent of the price you enter. The 3% shown is an example value, not an average for your area.
- Mortgage insurance appears only if you enter a rate, and it is applied when the down payment is under 20% of the price. It is not removed over time.
- Savings grow at the monthly equivalent of the APY you enter, with the deposit added at the end of each month. Taxes on interest are ignored.
- Not modeled: property tax, homeowners insurance, HOA dues, points, seller credits, loan programs with their own down payment rules, and your credit or income.
- This is an estimate for planning, not a loan offer or financial advice.
Frequently asked questions
How much down payment do I need for a house?
It depends on the loan program, the lender and your finances. This calculator shows the cash and the payment for 3% to 25% down, so you can compare the trade-offs. Your lender will tell you the minimum for the loan you apply for.
Is 20% down required?
Not always. Lenders commonly charge mortgage insurance when the down payment is under 20% on conventional loans, but programs and rules vary. The table shows the payment with and without insurance if you enter a quoted rate.
How is the cash needed at closing calculated?
It is the down payment plus closing costs, which here are a percent of the home price that you set. On a $400,000 home with 10% down and 3% costs, that is $40,000 plus $12,000, or $52,000.
How long will it take to save my down payment?
Add your savings so far and a monthly amount under More options. With $12,000 saved and $1,500 a month, a $52,000 goal takes 27 months. Adding 4% APY on the savings trims it to 25 months.
What if I enter a dollar amount instead of a percent?
Switch the down payment type. A $45,000 down payment on a $400,000 home is 11.25%, and the table adds a row for that figure so it sits in order with the standard levels.
Why can the down payment not equal the price?
With no loan there is no payment to calculate. The down payment must be less than the price. A cash purchase has no mortgage, so a mortgage calculator does not apply to it.