Rent vs Buy Calculator

Buying has large upfront costs (down payment, closing costs) and selling costs at the end — over a short horizon, those fixed costs aren't amortized over enough years to be beaten by the relatively slow, compounding advantage of home equity and appreciation.

It's crediting the renter with what the down payment would have earned elsewhere — a higher assumed return makes renting look better since that opportunity cost of a buyer's tied-up cash grows faster; a lower one narrows or eliminates renting's advantage.

Only if you ignore what the money not spent on a down payment, closing costs, property tax, insurance and maintenance could otherwise be doing — a renter who actually invests that difference isn't losing it, they're compounding it elsewhere instead of in home equity.

Mortgage interest tax deductions, rent control or lease-renewal uncertainty, the value of not having a landlord, moving costs, and any change in interest rates or home prices beyond a single steady assumption — all real factors this simplified comparison doesn't capture.

Because they are held flat by default, and that is the single biggest assumption on this page — which is why it is now a slider. Property tax, maintenance and insurance are all worked out from the price you paid and, at 0%, never move again, while rent compounds at whatever growth rate you set. Half the comparison is escalated and half is not until you say otherwise.

Part of that is right: a fixed-rate mortgage payment really is flat, and some places cap how fast a tax assessment can rise. But maintenance on a house that is appreciating is not flat, and insurance has outrun general inflation for a decade. Escalating those three at the same 3% this page already applies to rent moves the break-even from year 19 to year 30; at 4% a year, buying never catches up inside thirty years at all. The default seven-year verdict barely moves — but the break-even year, which is the number most people actually want, swings by more than a decade. Drag the slider and watch it. Measured in rentbuy_model.py.

The value of one assumption at which the two net costs tie at your horizon, with everything else held where you have it. The sensitivity grid shows the same thing as a picture; the flip points say it as a number: buying wins if the house appreciates faster than this, renting wins if your investments return more than that. If either is within a point of your own guess, you are not looking at a verdict, you are looking at a coin.

The exact same calculation this page already runs, repeated across a range of home-appreciation and investment-return guesses instead of just your one chosen pair — both genuinely uncertain numbers nobody can know in advance. A grid that's mostly one colour means the verdict barely depends on getting those guesses right; a mixed grid means the "answer" is really just one plausible outcome among several, and the honest response to "should I buy or rent" is "it depends which of these turns out true."