Down payment calculator
Estimate cash needed before a home purchase.
- Formula and assumptions shown
- Table and CSV export
- Runs in your browser
How it works
Choose a down-payment percentage and closing-cost percentage for the home price. The calculator adds those two amounts, subtracts current savings to show the gap, and models how monthly deposits plus an entered savings rate may close it.
Cash target = home price × (down-payment percentage + closing-cost percentage); gap = max(target − current savings, 0); each month, savings = prior savings × (1 + annual savings rate ÷ 12) + monthly deposit.
The target is your scenario, not a lender minimum or a local closing-cost estimate. The time result assumes the home price and target stay fixed while savings earn the entered rate.
Assumptions
- The down-payment and closing-cost percentages are applied to the same entered home price.
- The savings rate is divided by 12 and stays constant; monthly deposits are added after monthly interest.
- The home price and cash target do not change during the savings projection.
- Assistance programs, local fees, taxes, investment risk, and changes in home price are excluded.
Worked example
$350,000 with a 20% down-payment target
A 20% down-payment target plus 3% estimated closing costs gives a cash target of $80,500. With $25,000 saved, $1,500 added monthly, and a 3% savings-rate assumption, the model reaches the target in 35 months.
Step by step
- Down payment. $350,000 × 20% = $70,000.
- Closing costs and cash target. $350,000 × 3% = $10,500 of estimated closing costs. $70,000 + $10,500 = $80,500 cash target.
- Savings gap. $80,500 − $25,000 already saved = $55,500 still to save.
- Monthly growth. The 3% savings rate becomes 3% ÷ 12 = 0.25% a month. Each month the balance is multiplied by 1.0025 and then $1,500 is added. After 34 months the balance is $80,375.99, just short; after 35 months it is $82,076.93.
- Time to target. The target is first reached in month 35 (2 years 11 months). With no interest it would take $55,500 ÷ $1,500 = 37 months, so the interest saves 2 months.
How to read your result
Cash target is the down payment plus closing costs at the percentages you entered, which is the cash needed at closing in this scenario. Target down payment shows the down payment part alone; the loan in this scenario would be the home price minus that amount. Savings gap is the cash target minus current savings, or $0 when savings already cover it. Time to target counts whole months of deposits and interest until the balance first reaches the target, and it reads Beyond 600 months when the plan never gets there within 50 years.
The table lists the down payment, closing costs, cash target, and current savings. The target does not include moving costs, an emergency fund, or cash reserves some lenders require after closing, and it assumes the home price stays fixed while you save. If prices rise during the saving period, the same percentages produce a larger target.
What changes the result most
- Down payment percentage
- A 10% down payment instead of 20% lowers the cash target to $45,500 and the time to 13 months, but it means borrowing $35,000 more, which usually brings mortgage insurance on a conventional loan.
- Monthly savings
- Saving $2,000 a month instead of $1,500 reaches the $80,500 target in 27 months, 8 months sooner.
- Savings interest rate
- Over a three-year horizon the rate matters less than the deposits: at 0% the target takes 37 months and at 5% it takes 33 months, compared with 35 at 3%.
Questions
Does a larger down payment always save money?
It reduces the modeled loan amount, but it also uses more cash. Compare payment, interest, fees, liquidity, and your own priorities.
Does the savings-rate assumption change my target?
No. It affects only the modeled time to reach the target. The target itself comes from home price and the two percentages you enter.
Does this tell me the required down payment?
No. It calculates the target you enter. Providers and loan programs can apply different requirements.
How much down payment do I need for a house?
It depends on the loan program and the lender. Some conventional loans allow as little as 3% down, FHA loans allow 3.5% with a credit score of 580 or higher, and VA and USDA loans can require no down payment for eligible borrowers. On a conventional loan, putting down less than 20% usually means paying private mortgage insurance. Lenders can set higher minimums, so the calculator uses the percentage you enter.
How do you estimate closing costs?
Before you have a quote, a percentage of the price works as a placeholder; this calculator uses whatever percentage you enter, 3% by default. After an application, the Loan Estimate itemizes lender fees, appraisal, title charges, prepaid interest, escrow deposits, and government recording fees and transfer taxes. Transfer taxes in particular vary widely by state and locality. Replacing the placeholder with the Loan Estimate total gives a more reliable target.
More in Home & mortgage
Sources
These references explain the concepts behind the calculation. They do not endorse this site. Estimates leave out any cost or condition you did not enter.