Down Payment Calculator
Work out how much you need to put down on a home — and how long it will take to save it.
How to use this calculator
Enter the price of the home you are aiming for, then choose the down payment percent you plan to put down — 20% avoids private mortgage insurance, but many buyers put down less. Add what you have saved so far, how much you can set aside each month, and the interest rate (APY) your savings earn. The calculator shows the dollar down payment you need, how far you still have to go, and how many months of saving it will take to get there.
How this is calculated
Your down payment needed is simply the home price multiplied by your chosen percent. We then start from your current savings and step forward month by month: each month we add your monthly contribution and apply one-twelfth of your APY to the running balance. We count the months until the balance reaches your target. Interest earned is the growth your savings pick up along the way, on top of what you deposit. If the goal is still out of reach after 50 years we stop and suggest saving more.
Educational estimate, not financial advice — see our disclaimer.
A worked example
Say you want a $400,000 home and plan to put down 20%, so your target is $80,000. You already have $15,000 set aside and can save $1,000 a month in an account paying 4% APY. Starting from $15,000, each month adds your $1,000 deposit plus a little interest. It takes roughly five years of steady saving to cross the $80,000 line, and the interest earned shaves a few months off compared with stuffing the cash under a mattress. Bump your monthly saving to $1,500 and you would reach the goal noticeably faster.
How much down payment do you really need?
The classic target is 20% because it lets you skip private mortgage insurance (PMI) and usually unlocks better loan terms. But it is not a hard requirement. Conventional loans can go as low as 3% down, FHA loans around 3.5%, and some VA and USDA loans allow 0% for eligible buyers. A smaller down payment gets you into a home sooner, but means a larger loan, higher monthly payments, and — below 20% — an added PMI cost until you build enough equity. Our PMI calculator can estimate that extra cost so you can weigh waiting longer against buying now.
Tips to save faster
- Automate it — set up an automatic transfer on payday so the money is gone before you can spend it.
- Earn yield — keep the cash in a high-yield savings account or money market fund, not a checking account earning nothing.
- Trim a target — a slightly cheaper home, or a 10% down payment with PMI, can move your timeline forward by years.
- Windfalls help — tax refunds, bonuses, and gifts can take big bites out of the gap.
Treating the down payment as a dedicated savings goal makes the timeline concrete. A savings goal calculator can help you reverse-engineer the monthly amount needed to hit a specific date.