Enter your numbers once. This tracks your home equity against a renter's invested savings, month by month, so you can see if — and when — the two paths cross.
How this calculator works
Every rent-vs-buy argument comes down to one question most calculators skip: if renting is cheaper than owning each month, does the renter actually invest the gap? If they do, a renter with a good index fund can finish ahead of a homeowner for a surprisingly long time. If they don't, the homeowner wins almost by default, because a mortgage is a forced savings plan. This calculator lets you set that answer with the "monthly difference invested" slider and then runs both lives month by month.
Owning cost is the principal-and-interest payment plus "other monthly costs" — property tax, insurance, PMI and HOA. When owning costs more than renting (the usual case in year one), the difference is what the renter can invest. When rent is higher, the sign flips and the buyer is the one banking the gap.
The chart draws both lines for as many years as you choose and marks the month they cross. That crossover is the real break-even, and it moves a lot with three assumptions: home appreciation (3.5% default — close to the long-run national average, but Buffalo isn't Boise), investment return, and how long you'll actually stay. Sell within four or five years and the selling costs alone usually hand the win to renting; stay fifteen and the mortgage paydown plus appreciation usually wins it back.
It doesn't model rent increases, tax deductions, or maintenance beyond the "other costs" field — add a realistic maintenance figure there (1% of the home's value per year is the common rule) if you want a harsher test of buying. And it says nothing about whether you can afford the house in the first place; that's the Home Affordability calculator's job.
Be honest. The slider starts at 100% — every dollar renting saves you goes into investments, automatically. Most people don't do that; 50% is fair for someone with an automatic transfer set up, and 0% is what happens without one. Try both and watch how far the crossover moves.
Because selling in month one would cost you the 7% in commissions and closing, and you've barely paid down principal. That early dip is the strongest argument for not buying a home you might leave in two years.
Nationally, home prices have grown roughly 3–4% a year over long periods, with big swings by decade and by metro. Use 3% for a conservative test (the default is 3.5%), and look at what your own county has actually done over the last 20 years — not the last three.
No. Since the 2017 tax changes, most households take the standard deduction and get no benefit from mortgage interest, so leaving it out is the realistic default. If you itemize, the effect is a modest boost to the buyer's side.
Last reviewed September 2026. Read our methodology for every source and assumption, and the calculator disclaimers for what these estimates are and aren't.