What Is a Cap Rate in Real Estate? How to Calculate It

What Is a Cap Rate in Real Estate?

A cap rate, short for capitalization rate, is a property's net operating income divided by its price, expressed as a percentage. It answers one question: for every dollar you pay for a building, how many cents of income does it throw off in a year, before financing. A property producing $500,000 of NOI that sells for $10 million has a 5% cap rate. The same building at $8.3 million would be a 6% cap rate.

The cap rate is the quickest way to compare properties on the same terms. Because it uses NOI, which sits above debt service, the cap rate strips out how each buyer chooses to finance the deal. Two investors looking at the same property, one paying all cash and one borrowing 65%, see the same cap rate. That is what makes it useful for pricing: it isolates the yield of the real estate itself from the capital structure layered on top.

Investors talk about two versions of the same number. The going-in cap rate is your entry yield, current NOI over the purchase price. The exit cap rate is the yield you assume a future buyer will accept, applied to your projected NOI at sale. The gap between the two is one of the biggest drivers of returns, which is why underwriters scrutinize the exit assumption as hard as the entry.

The Cap Rate Formula and a Worked Example

The formula is simple. The work is in the inputs.

Cap Rate = Net Operating Income ÷ Purchase Price

Rearranged, the same equation gives you the other two variables. If you know the cap rate the market is paying and the property's NOI, you get value: Value = NOI ÷ Cap Rate. If you know the price and the cap rate, you get the implied NOI. Underwriters flip between these three forms constantly.

Take a 40-unit apartment building. The trailing 12-month statement shows $780,000 of effective gross income and $335,000 of operating expenses, so NOI is $445,000. The seller is asking $8.9 million.

• Cap rate at asking = $445,000 ÷ $8,900,000 = 5.0%
• If comparable buildings trade at a 5.5% cap rate, the value implied by that yield is $445,000 ÷ 0.055 = $8.09 million, about $810,000 below asking.
• If you push NOI to a stabilized $500,000 through rent growth and expense cuts, the same 5.5% market cap rate supports $500,000 ÷ 0.055 = $9.09 million.

That last line is the whole value-add thesis in one calculation: grow the numerator, hold the market cap rate roughly constant, and the value moves. Notice how sensitive the answer is to NOI. A single mis-stated expense line changes the price by hundreds of thousands of dollars, which is why the NOI feeding a cap rate has to be normalized before you trust the yield.

What Is a Good Cap Rate?

There is no universal answer. A good cap rate is one that fairly compensates you for the risk, quality, and growth of a specific asset in a specific market. The right way to read a cap rate is as a price signal: a low cap rate means the market is paying up for safety, quality, or expected rent growth, and a high cap rate means the market is demanding a bigger yield to take on more risk or weaker fundamentals.

Whether high or low is good depends on which side of the table you sit on. A buyer wants a higher cap rate, because it means paying less for each dollar of income. A seller wants a lower cap rate, because it means a richer price. The table below shows the ranges that were typical across asset classes in strong markets as of 2026. Treat these as orientation, not gospel: cap rates reprice with interest rates and vary widely by metro and vintage.

A high cap rate is not automatically a better deal. It usually means the market has priced in a problem: soft demand, tenant credit risk, deferred capital needs, or a submarket that is not growing. A suburban office building at a 9% cap rate looks like a rich yield until you account for the re-leasing costs and vacancy risk that put it there. The discipline is to ask why a cap rate sits where it does, not to chase the highest number on the page.

The other trap runs the opposite direction. A seller can manufacture a low, attractive-looking price-per-yield by inflating NOI: understating management fees, showing pre-reassessment property taxes, or omitting a reserves line. The stated cap rate is only as honest as the NOI underneath it, so the first job in any deal is to normalize the operating statement before you trust the yield. See our guide on reading a T12 for how that normalization works.

Cap Rate vs IRR

The cap rate and the internal rate of return answer different questions, and confusing them is one of the most common mistakes in CRE analysis. The cap rate is a snapshot: one year of NOI over price, unlevered, ignoring what happens after year one. IRR is the movie: it accounts for every cash flow across the hold, including financing, annual distributions, and the proceeds when you sell.

Because IRR includes debt and the exit, a low going-in cap rate can still produce a strong IRR. A property bought at a 5% cap rate can deliver a 15% IRR if you add moderate debt, grow NOI, and sell into a market that holds or compresses the exit cap rate. The reverse is also true: a fat 8% going-in cap rate can produce a mediocre IRR if rents stall and the exit cap rate expands against you.

Use the cap rate to price the asset today and to compare deals on the same footing. Use IRR to judge the full return of your specific business plan and capital stack. Neither replaces the other. For a full side-by-side, see cap rate vs IRR.

What Moves Cap Rates

Cap rates are not fixed properties of a building. They are prices set by the market, and they move for three main reasons.

Interest Rates

This is the biggest lever. When benchmark rates rise, borrowing gets more expensive and safe alternatives like Treasuries pay more, so investors demand a higher yield from real estate to compensate. Cap rates expand and prices fall even when NOI is flat. The 2022 to 2024 repricing was almost entirely a rate story: NOI held up or grew, but cap rates widened by 75 to 150 basis points across most asset classes, and values dropped accordingly. When rates fall, the reverse happens and cap rates compress.

Expected Rent Growth

Buyers pay a lower cap rate for income they expect to grow. A Sun Belt apartment market with strong in-migration and rising rents will trade at a tighter cap rate than an identical building in a flat market, because part of the return is expected to come from future NOI growth rather than current yield. This is why the same physical asset can carry very different cap rates in two cities.

Risk of the Income

The more certain the cash flow, the lower the cap rate. A newer multifamily property with staggered leases and strong occupancy carries less risk than a single-tenant building whose lease expires in two years, so it trades tighter. Tenant credit, lease term, asset age, capital needs, and market depth all feed into the risk premium the market bakes into the cap rate.

How AcquiOS Derives the Cap Rate Automatically

The hard part of a cap rate is never the division. It is producing a trustworthy NOI to divide. AcquiOS handles that end to end. You upload the offering memorandum, and the platform extracts the T12 and rent roll straight from the PDF, no manual re-entry.

From there it normalizes: it reconciles scheduled rent on the rent roll against the income on the T12, flags one-time items, grosses up management fees and payroll to market rates, and adjusts property taxes for the likely post-sale reassessment. The result is a stabilized NOI you can defend, not the seller's version. Divide that by the asking price and you have a going-in cap rate that reflects reality.

AcquiOS then checks the number against the market. It validates your going-in and exit cap rate assumptions against actual trades for comparable properties in the same submarket, so you can see whether a 5% going-in cap is aggressive or fair for that asset. Every figure traces back to the source line in the OM, so when the investment committee asks where the cap rate came from, you can show them. What used to take an analyst an afternoon of spreadsheet work happens in minutes.

For how this fits the broader workflow, see the guide to underwriting a multifamily deal and the assumption validation feature.

Frequently Asked Questions

How do you calculate a cap rate?

Divide net operating income by the purchase price. A property that produces $500,000 in NOI and sells for $10,000,000 has a 5% cap rate. Because it uses NOI, which sits above debt service, the cap rate measures the unlevered yield of the property and ignores how any individual buyer finances the deal.

What is a good cap rate in real estate?

There is no single good cap rate. It depends on the market, the asset class, and the risk of the income. Stabilized multifamily in a strong metro often trades at 4.5% to 5.5%, while older suburban office can sit at 8% to 10% or higher. A higher cap rate means a higher current yield but usually more risk or weaker rent growth, so a good cap rate is one that fairly prices those factors for the specific asset.

Is a higher or lower cap rate better?

It depends on your side of the deal. A buyer prefers a higher cap rate because it means paying less for each dollar of income. A seller prefers a lower cap rate because it means a higher price. In general, a low cap rate signals a safer, higher-quality, or faster-growing asset, and a high cap rate signals more risk or slower growth.

What is the difference between a cap rate and IRR?

A cap rate is a single-year, unlevered snapshot: NOI over price. IRR is the annualized return across your entire hold, including financing, yearly cash flow, and the sale proceeds. A 5% going-in cap rate can still deliver a 15% IRR once you add debt, grow NOI, and sell. Use the cap rate to price the asset and IRR to judge the full return of your plan.

What causes cap rates to rise or fall?

Three forces move cap rates: interest rates, expected rent growth, and the risk of the income. Rising rates push cap rates up and prices down even when NOI is flat. Strong expected rent growth pulls cap rates down because buyers pay more for income they expect to grow. Higher risk, from tenant credit to short lease terms, pushes cap rates up.