Seven rent vs. buy calculators, compared on one scenario

Written by Jonathan Nyst

Most rent-vs-buy calculators are lead-generation funnels with a math veneer; a handful are genuinely rigorous. We tested seven on the things that actually decide the answer — opportunity cost, selling costs, taxes, and whether the math is documented. One of the seven is ours. We say so immediately, we do not rank it against the others — a vendor grading its own tool is worth nothing to you — and we describe it in the same terms as the rest so you can weigh it yourself. If you came here looking for a free version of the New York Times calculator, that gets its own section below — including the two things the Times still does better.

How did we compare these calculators?

On four things, in order of weight: methodology completeness (does it model the invest-the-difference alternative, round-trip transaction costs, and real tax rules?), transparency (is the math published?), UX, and price. Disclosure up front: we built one of these tools. It appears in the table with the others and gets its own clearly separated section at the end of the list — described, not scored — and every claim below is specific enough for you to verify against each tool’s live page.

Methodology gets the most weight because it is where calculators quietly disagree. A tool that compares mortgage payment to rent will say buying wins almost everywhere. In our model’s default scenario — $420,000 home, $2,100/month comparable rent, 20% down, 6.5% thirty-year mortgage — the owner’s true first-year cost is $3,067/month once property tax, insurance, and maintenance are counted, not the $2,124 principal-and-interest figure. Any calculator that hides that $943/month gap, or forgets that the renter can invest the difference, fails before UX even matters.

How do the seven calculators differ?

Mostly in what they leave out. Only two of the seven — the New York Times/Upshot calculator and ours — invest the cheaper side’s savings symmetrically and report a tipping-point rent; the Times is the reference methodology and sits behind a subscription. NerdWallet is the most complete of the big-brand free tools, The Measure of a Plan is the most transparent if you will work in Excel, and the rest are cash-flow comparisons with varying amounts of tax and selling-cost realism.

Feature table verified against each tool’s live page, July 2026. Rows are in no particular order beyond grouping the two tipping-point tools first.

Tool by tool: what each one gets right, and what it skips

New York Times / The Upshot — the reference standard, behind a paywall

The Upshot calculator, rebuilt in May 2024, is what every other tool gets measured against: opportunity cost applied to both upfront and recurring cash flows at an editable return, transaction costs in both directions, and post-2017 tax law including the standard-deduction problem. Its slider-driven sensitivity UX remains the best anywhere. What it skips: free access — it is subscriber-gated, the only paid tool here — and its assumptions live inside the tool rather than in a standalone methodology document. If you already subscribe, use it, ideally alongside a free tool as a cross-check. The free NYT-style section below walks through what it got right and what a free tool can and cannot replicate.

NerdWallet — the most complete big-brand free calculator

NerdWallet’s tool credits opportunity cost on any cash either path could have invested, discounts everything to today’s dollars, and runs on defaults we recorded in July 2026 (6% investment return, 3% inflation, maintenance at 1.5% of home value). What it does well: honest inflation handling and readable output. What it skips: tax realism — one marginal-rate field, with no check on whether your itemized deductions actually clear the standard deduction, which flatters buying for most filers — and sale-side transaction costs are not clearly surfaced in the results.

The Measure of a Plan — most transparent, least convenient

A free downloadable Excel model in which every formula is inspectable — the only entry here with nothing hidden at all. It models the invested down payment and buying fees, agent commissions at sale, the mortgage-interest tax shield, and mortgage insurance. What it skips: convenience and freshness. It is a spreadsheet, its defaults lean Canadian (CMHC mortgage insurance), and the last revision (v3.2) shipped in March 2023, so 2026 US tax parameters need manual updating.

SmartAsset — excellent on costs, vague on opportunity cost

SmartAsset’s calculator itemizes ownership costs better than anyone: location-based closing costs down to the appraiser’s fee, local property taxes, PMI, HOA, then realtor fees and capital gains tax at sale, presented as a clean break-even year. What it does well: cost realism and federal/state/local tax awareness. What it skips: its opportunity-cost assumptions are documented nowhere we could find, its break-evens run noticeably shorter than NYT’s or NerdWallet’s on comparable inputs, and the page’s real job is routing you to a financial advisor.

Calculator.net — more rigorous than it looks

Behind Calculator.net’s dated design is a surprisingly complete input set: average investment return, marginal federal and state tax rates, filing status, closing costs on both purchase and sale, appreciation, and rent growth. What it does well: breadth of inputs, a plain break-even statement, fast and free. What it skips: any explanation of how those tax fields are applied — there is no visible standard-versus-itemized logic, which overstates the owner’s tax benefit for the roughly nine in ten filers who take the standard deduction (88.6% of returns in tax year 2022, per IRS Statistics of Income) — and the UX is a dense form wrapped in ads.

Zillow — a fine first pass, not a decision tool

Zillow’s consumer calculator produces a fast break-even readout (buying becomes cheaper after five years and some months) sitting on top of a genuinely decent research methodology that invests the renter’s forgone down payment and closing costs. What it does well: speed and zero learning curve. What it skips: the consumer tool exposes almost none of its assumptions, the research model invests the renter’s cash at a conservative near-risk-free rate — which systematically shortens break-evens compared with an equity-market assumption — and the page is engineered to move you toward listings and loan officers.

Ours: RentVsBuyMath.com — described in the same terms, not scored

This is our tool, so treat everything in this section as a claim to check rather than a verdict. Here is the falsifiable version. Our engine models opportunity cost symmetrically: whichever side pays less in a given month invests the difference — most calculators only credit the renter, which quietly biases results toward renting. Taxes are modeled as they actually work in 2026: the standard-versus-itemized delta rather than a flat deduction, the $40,400 SALT cap, the $750,000 mortgage-interest cap, the Section 121 exclusion on home-sale gains, and capital gains tax on the renter’s portfolio. It handles PMI with automatic cancellation, full selling costs, all-cash purchases, and horizons past mortgage payoff. Every formula is documented on our methodology page, and the engine passes 188 tests including 10 audit vectors computed independently of the code. What it skips: location-aware defaults. You bring your own property-tax rate and insurance quote, where NYT and SmartAsset prefill from your metro — though our rent-vs-buy by metro table now gives Zillow-based starting prices and rents for the largest US metros. It is free, with no account and no lead-gen. If you do not trust us yet — reasonable — run the Times’ tool or NerdWallet’s with identical inputs and compare.

What about Bankrate and the Mortgage Professor?

Neither made the list, for different reasons. Bankrate’s calculator compares upfront and monthly cash flows — down payment and closing costs versus deposit, mortgage versus rent — but we could not verify that it models opportunity cost, sale-side costs, or tax detail, and it publishes no methodology. A cash-flow comparison cannot answer the wealth question, which is the question. The Mortgage Professor is the sadder omission: founder Jack Guttentag, Wharton emeritus and the most rigorous consumer advocate mortgage finance ever had, died in February 2024 at age 100. The site carries on as a legacy mortgage-shopping project, but its calculators reflect an earlier tax regime. Treat it as an archive worth reading, not a maintained tool.

Is there a free alternative to the NYT rent-vs-buy calculator?

Yes. The calculator on this site implements the same core model The Upshot popularized — whichever side pays less each month invests the difference, and the headline answer is the rent at which the verdict flips — free, with no paywall, account, or email required. It adds an automatic sensitivity table, an open-source engine, and currency-agnostic inputs. We are not affiliated with the Times.

RentVsBuyMath.com is not affiliated with, endorsed by, or connected to The New York Times Company in any way. “The New York Times” and “The Upshot” are its trademarks; we name them only to credit and compare. The original interactive lives at nytimes.com and requires a subscription — if you have one, it is still worth using.

What made the NYT calculator the gold standard?

Three design decisions, rare in 2014 and still rare now. The answer updated live as you moved any slider. The verdict was a single number — the monthly rent above which buying wins — rather than a vague score. And it treated opportunity cost symmetrically, investing the cheaper path’s savings instead of assuming a renter burns the difference. First built in 2007 and rebuilt by The Upshot in 2014, it answered with a sentence people still quote: if you can rent a similar home for less than $X a month, renting is the better deal. That one number compresses fifteen assumptions into something you can check against real listings.

The symmetry is the part most imitators skip. In our default scenario the owner’s true first-year cost is about $3,067 a month against $2,115 all-in for the renter; an honest model invests the renter’s monthly savings on top of the $84,000 they never handed over as a down payment — and, once rent growth pushes the renter’s cost above the owner’s, invests the owner’s surplus too. Most calculators run this logic in one direction, or not at all. The third trick was progressive disclosure: a handful of big sliders up front, with maintenance, closing costs, and taxes tucked into collapsible sections carrying sane defaults. We copied that pattern deliberately.

How do the four best-known calculators compare feature by feature?

Only the Times and RentVsBuyMath compute a tipping-point rent and invest both sides’ savings symmetrically. Only the Times charges for access. Only RentVsBuyMath publishes its full engine and runs an automatic sensitivity analysis. Snapshot as of July 2026:

“Form-based” means you fill in fields and read a results panel; the verdict doesn’t reprice under your cursor. Competitors change their tools, so treat this as a mid-2026 snapshot — including the last row, where the Times beats us.

What does the NYT calculator still do better?

Two real things: inflation-adjusted display and editorial polish. The Times can present results in today’s dollars, which makes 25-year comparisons far more intuitive; our engine reports nominal dollars, so the thirty-year figure below overstates its present-day purchasing power. And a decade of newsroom craft shows in their prose, defaults, and slider feel. If you subscribe, use both: two tools built on symmetric opportunity-cost accounting should agree directionally, and where they differ you’ll learn something about defaults — their maintenance and closing-cost assumptions versus ours. If either disagrees with a lender’s calculator, trust the one that invests the down payment.

What does a tipping-point answer look like at 2026 rates?

In our model’s default scenario — $420,000 home, 20% down, 30-year fixed, 10-year stay, 3% home appreciation, 2.5% rent growth, 7% investment return, standard deduction — the tipping-point rent at a 6.5% mortgage is $2,468 a month. Rent a comparable home for less and renting-plus-investing wins; pay more and buying wins.

The tipping point moves mostly with the mortgage rate. Here is the same scenario across the rate range, with the price-to-rent ratio each threshold implies:

Freddie Mac’s survey put the 30-year average near 6.7% in mid-2026, so the middle rows are today’s reality. Our default comparable rent of $2,100 — 0.5% of the home’s price per month — sits below the $2,468 threshold, and renting wins by about $67,000 over ten years. Rerun the identical house at the 4% rates of 2021 and buying wins by about $38,000, breaking even in year six. Nothing about the house changed; the rate flipped the answer, which is the story of the whole 2026 market. Every figure in this table is recomputed from the engine on each deploy and published, with the full rate ladder, on the numbers page.

The ratio column explains the geography. A $220,000 home renting for $1,600 a month (ratio ≈ 11.5, or 0.73% of price per month) clears the bar easily: buying wins in our model. A $1.1 million home renting for $3,800 (ratio ≈ 24, or 0.35%) doesn’t come close: renting wins by roughly $561,000 over fifteen years, even for a married couple itemizing deductions. And when rent sits far below the tipping point, waiting doesn’t rescue buying — in the default scenario renting’s lead grows from about $49,000 at five years to $67,000 at ten to $389,000 (nominal) at thirty. The horizon logic gets its own treatment in when does buying beat renting.

Why do good calculators disagree on the same inputs?

Because the disagreement is in the assumptions, not the arithmetic — chiefly what return the un-spent cash earns, and how taxes are handled. Feed every tool on this page the identical scenario and the verdicts will still differ, because each one silently chooses an investment return, an inflation treatment, a maintenance rate, and a tax model. The table above shows why a calculator’s rate default alone can decide its verdict.

One more reason documentation matters: in our default scenario no single ±1-point assumption change flips the verdict, but at 4% rates a single point of appreciation or mortgage rate does — precisely the regime where a tool with hidden defaults can mislead you. Our sensitivity table prints that fragility picture automatically; the Times lets you discover it by dragging sliders one at a time; the rest of the field does not surface it at all. For where that boundary sits, see when buying beats renting and our 2026 rent-vs-buy outlook.

Run your own numbers

Comparisons are opinions; your inputs are not. Open our calculator preloaded with the default scenario above, then replace every number with your own — your metro’s prices, your actual rent quote, your honest guess at how long you will stay. If our verdict differs from NerdWallet’s or the Times’, that disagreement is the most informative number on this page: find the assumption that causes it, and you have found what your decision actually depends on. The calculator is currency-agnostic, and every tax input can be zeroed if US rules do not apply to you.