Comprehensive Guide
Learn more in our Investing Guide.
How it works
house hacking calculator takes your inputs and produces net monthly housing cost, savings vs renting, annual savings, equity built (year 1). Compare house hacking scenarios — live in one unit, rent others. Calculate net housing cost and savings vs traditional renting. You provide 7 inputs: Property Price (currency, in dollars) (default: 400000 dollars); Down Payment % (percent, in percent) (default: 5 percent); Number of Units (number) (default: 2); Market Rent for Your Unit (currency, in dollars) (default: 1500 dollars); Rent from Other Units (currency, in dollars) (default: 1500 dollars); Mortgage Rate % (percent, in percent) (default: 7 percent); Monthly Expenses (all units) (currency, in dollars) (default: 800 dollars). The calculator returns 4 outputs: Net Monthly Housing Cost (the primary result); Savings vs Renting (a secondary output); Annual Savings (a secondary output); Equity Built (Year 1) (a secondary output). Investment calculations rest on a few variables — principal, return rate, time, and compounding — but their interaction is non-linear enough that intuition alone gets the answer wrong more often than not. This tool runs the real formula with your inputs and shows the numbers that matter, not the rounded approximations from a textbook. With the default values, net monthly housing cost is computed from the interaction of every input field — change any one of them and the result updates immediately, so you can stress-test different scenarios without re-entering the whole form. Adjust the inputs to match your real financial situation. The defaults are realistic starting points, but every person's circumstances differ — your actual income, expenses, rates, and timelines will produce a different answer. Use the tool iteratively: start with the defaults, then change one variable at a time to see which factor has the largest impact on your outcome.Tips
- Start with the default values to see a baseline result, then change one input at a time to understand which factor matters most for your outcome.
- Replace every default with your actual number — estimates and rules of thumb produce estimates, not answers. Pull your real figures from pay stubs, statements, or account dashboards.
- Use a conservative return rate (5-6% rather than the historical 10%) for planning purposes. Markets have long flat stretches, and planning on the average sets you up for a shortfall.
Frequently asked questions
What is house hacking?
House hacking is buying a multi-unit property (duplex, triplex, fourplex), living in one unit, and renting the others. Rental income offsets or eliminates your housing cost.
Do I need 20% down for house hacking?
No! FHA loans allow 3.5% down on owner-occupied 1-4 unit properties. VA loans allow 0% down. This is the biggest financial advantage of house hacking.
How accurate are the calculator results?
The math is exact — the same formulas a financial professional would use by hand. The precision of the output depends entirely on how realistic your inputs are. Use your actual numbers rather than estimates when possible. The defaults are reasonable starting points, but your real income, rates, and timeline will produce a different result.