Renting and investing is ahead by $67,000 after 10 years.

Should you buy, or rent and invest the difference?

Put your numbers in. Get the honest answer, with every formula public and nothing trying to sell you a mortgage.

Open sourceNo sign-upEvery formula documented
You pay in rent
$a month
Or you buy at
$
%
years
Renting winsyou would have
$313,000at year 10
+$67,000 vs buying

Assumes the $810 a month difference is invested at 7%, averaged over the stay. Rent must be for a place comparable to the home.

The answer after 10 years

+$67,000

Renting and investing ends that far ahead.

That is the difference in what you are worth at the end of the stay - not what you paid, and not what the home is worth.

Where the $67,000 comes from

Both paths at the end of the stay, and the one number that decides which is which.

Rent & invest
$313,000

Your money if the monthly difference is invested, every month.

Ahead by $67,000
Buy
$246,000

Your money with the equity kept and every cost of owning counted.

Behind
The tipping point
$2,468 a month

Pay more than this in rent and buying starts to win - about 0.59% of the home's value a month.

An honest calculator, not a sales tool

Most rent-versus-buy calculators are published by people who profit when you buy. This one has nothing to sell, and it takes the renter's side of the maths as seriously as the owner's.

Symmetric opportunity cost

Whichever path costs less in a given month, the difference is invested by the person on that path. Most calculators only let the buyer build wealth and quietly assume the renter spends the difference.

The full cost of owning

Interest, property tax, insurance, maintenance, HOA, mortgage insurance, closing costs and selling costs. Not just the mortgage payment.

Real tax rules

Standard deduction versus itemising, the $750,000 mortgage-interest cap, the SALT limit, capital gains, and the Section 121 home-sale exclusion.

Honest about uncertainty

Every answer comes with the levers that would flip it. If the result sits on a knife edge, the page says so rather than projecting false confidence.

Open sourceEvery formula documentedNo sign-up, no data collected

Where the money actually goes

Every dollar each path spends in an average month of the stay. Solid acid is money that stays yours; grey is money that leaves for good.

Owningper month, averaged over the stay$3,180/mo
Mortgage interest$1,697Property tax$422Maintenance$401Home insurance$233Principal - stays yours$426

Owning keeps $426 a month.

Rentingper month, averaged over the stay$3,180/mo
Rent$2,353Renter's insurance$17Invested difference - stays yours$810

Renting keeps $810 a month.

Both bars total the same on purpose. Whichever path costs less each month, the difference is invested by the person on that path - so the comparison is like for like. What separates the two is not how much goes out, but how much of it stays yours: $426 a month owning against $810 a month renting.

The year by year

Where each path stands at the end of every year of the stay. The line that is ahead at the end carries the colour; both are labelled, and rent is always listed first.

Rent & invest aheadBuy behind

The two paths never cross inside this stay - the gap only widens.

What would change the answer

Nothing here flips it. A one-point move in home appreciation, investment return, rent growth or the mortgage rate all leave the same path ahead - the answer is not balanced on a knife edge.

Rates decide the answer

The mortgage rate moves the tipping point more than anything else you can change. Below is the rent at which buying starts to win, at each rate, holding your other assumptions fixed. Your row is highlighted.

Mortgage rateBuying wins aboveAs % of home value / moAt your rent, who wins
4.00%$1,890/mo0.45%Buying by $38,000
4.50%$2,003/mo0.48%Buying by $18,000
5.00%$2,117/mo0.50%Rent & invest by $3,000
5.50%$2,233/mo0.53%Rent & invest by $24,000
6.00%$2,350/mo0.56%Rent & invest by $46,000
6.50%your rate$2,468/mo0.59%Rent & invest by $67,000
7.00%$2,587/mo0.62%Rent & invest by $89,000
7.50%$2,708/mo0.64%Rent & invest by $111,000
8.00%$2,829/mo0.67%Rent & invest by $134,000

Percentages are the tipping rent divided by the home price, not by the loan - a distinction worth keeping straight, since the two differ by the size of your down payment.

Change every assumption

These are the defaults doing the work behind the answer. Every one is editable, and the whole page recomputes as you type. Nothing here is a secret.

The purchase

%
%
%
years

Cost of owning

% /yr
% /yr
$ /yr
$ /mo
% /yr
% /yr

Cost of renting

% /yr
$ /mo
month

Markets and tax

% /yr
% /yr
% /yr
% /yr
%
%

Keep your result

Your scenario as plain text, with the numbers and the assumptions behind them. Paste it into ChatGPT or Claude to talk through your own situation - the things this page cannot know, like how long you will really stay or how secure your income is.

RENT VS BUY - my scenario (https://rentvsbuymath.com)

Monthly rent:        $2,100
Home price:          $420,000
Mortgage rate:       6.50%
Length of stay:      10 years

RESULT AFTER 10 YEARS
Rent & invest:       $313,000
Buy:                 $246,000
Verdict:             renting & investing ahead by $67,000
Tipping rent:        $2,468 a month (0.59% of home value)

KEY ASSUMPTIONS
Down payment 20% · investment return 7% · home appreciation 3% · rent growth 2.5% · property tax 1.1% · maintenance 1% · selling costs 6% · inflation 2.5%
Assumes the $810/mo difference is invested every month, averaged over the stay.

WHAT I WANT TO TALK THROUGH
This model cannot know how long I will really stay, how secure my income is,
or what this home means to me beyond the money. Help me think about those.

Audit the math

Every year of the simulation, and what each path is worth at the end of it. Nothing is rounded away and nothing is hidden behind a chart.

YearRent & investBuyDifferenceHome valueLoan balance
1$114,000$74,000-$40,000$433,000$332,000
2$132,000$91,000-$42,000$446,000$328,000
3$151,000$107,000-$44,000$459,000$324,000
4$171,000$125,000-$46,000$473,000$319,000
5$192,000$143,000-$49,000$487,000$315,000
6$214,000$162,000-$52,000$502,000$309,000
7$237,000$182,000-$55,000$517,000$304,000
8$261,000$202,000-$59,000$532,000$298,000
9$287,000$224,000-$63,000$548,000$292,000
10$313,000$246,000-$67,000$564,000$285,000

Net worth is what you would hold in cash if you sold up and walked away at the end of that year - equity after selling costs and any tax, plus investments after capital gains.

Quick answers

The questions people ask most. Twenty more are answered with numbers on the FAQ page.

Is it cheaper to rent or buy right now?

At 6.50% on a $420,000 home with $2,100 rent over 10 years, renting and investing comes out $67,000 ahead. Change the rate and that can flip - the table above shows where.

How does this decide which side wins?

It simulates both paths month by month for your whole stay: the buyer pays the mortgage, taxes, insurance, maintenance, and PMI and builds equity; the renter pays rent and invests the down payment plus every month’s cost difference. Whichever side is cheaper in a given month invests the surplus — both directions. At the end, both sides "cash out" (selling costs and taxes included) and we compare net worth.

What rent makes buying the better deal?

At your numbers, $2,468 a month - about 0.59% of the home's value per month. Below that, renting and investing the difference stays ahead.

Does it account for taxes?

Yes — with current US rules: the standard deduction versus itemizing (mortgage interest capped at $750,000 of loan, property tax capped by the $40,400 SALT limit), capital-gains tax on the investment portfolio, and the Section 121 home-sale exclusion ($250k single / $500k married). Outside the US, set the tax fields to zero and use it as a pre-tax comparison in any currency.

Why do most calculators favour buying?

Three common shortcuts: they compare a mortgage payment to rent while ignoring taxes, maintenance, and selling costs; they don’t invest the renter’s down payment; and they never credit the buyer’s surplus when renting is dearer, or the renter’s when owning is dearer. We model the opportunity cost symmetrically and document every formula on the methodology page.

Is this financial advice?

No. It’s an educational model driven entirely by your assumptions — small changes can flip the answer, which is why we show a sensitivity table with every result. Use it to understand the trade-off, then talk to a professional who knows your situation.

Go deeper

The calculator answers one scenario. These answer the questions it raises - the shortcuts worth knowing, and how this model differs from the ones you have already tried.

More guides: Capital Gains on a Home Sale · The SALT Cap and Rent vs Buy · When Will Mortgage Rates Fall? · How PMI Actually Ends · What Selling a House Really Costs — and Why It Decides Rent vs Buy · Does the Mortgage Interest Deduction Still Matter? For Most Buyers, No · Does Buying a House Actually Build Wealth? Slower Than the Payment Suggests · Is Renting Throwing Money Away? No — Here Is What Both Sides Actually Burn · Should You Buy in an Expensive City? The Math Says Usually Not · Rent vs Buy in 2026: What Today’s Rates Do to the Math · Is Buying Always Better Than Renting? No — Here’s When Renting Wins