Cap Rate Calculator

Cap Rate Calculator: Work Out a Property's Return in Seconds

Cap rate, short for capitalization rate, is the number real estate investors reach for first when they're sizing up a rental or commercial property. It's a quick way to compare a duplex in one city to an office building in another, without getting lost in mortgage terms, down payments, or financing structure. This free cap rate calculator does the math for you, and it goes a step further than most tools you'll find online.

If you already know your property's net operating income, just type it in along with the property value and you're done. But if you don't have a clean NOI number yet, flip the switch to "Build it from rent and expenses" and the calculator will work it out for you from your rental income, other income, vacancy loss, and operating costs. You'll also get a reverse valuation, a gross rent multiplier, a sensitivity chart, and an optional cash-on-cash return if you plan to finance the deal.

What Is Cap Rate and Why Investors Use It

Cap rate answers one simple question: if you paid cash for this property, what percentage return would the income alone give you every year, before financing? The formula is Cap Rate = Net Operating Income ÷ Property Value, multiplied by 100 to get a percentage. A property worth 500,000 dollars generating 35,000 dollars in NOI has a cap rate of 7%.

The reason cap rate is so popular is that it strips out financing entirely. Two investors buying the exact same building, one with cash and one with a mortgage, get the exact same cap rate, since the calculation never touches the loan. This makes it a clean, apples-to-apples way to compare properties that might have very different financing setups, which is exactly why brokers, appraisers, and investors lean on it as a first screening tool.

How to Use This Calculator, Step by Step

Start with the property value, either what you're planning to pay or what the property is currently worth. Then handle the NOI. If you already have a clean number from a seller's financials or your own bookkeeping, choose "I know my NOI" and type it straight in.

If you'd rather build it from scratch, or you want to double-check a seller's numbers, switch to "Build it from rent and expenses." Enter the gross annual rental income at full occupancy, any other income like parking or laundry, your expected vacancy and credit loss percentage, and your annual operating expenses. The calculator subtracts vacancy loss from your gross income to get effective gross income, then subtracts operating expenses to land on NOI automatically. From there, everything else, the cap rate, the reverse valuation, the gross rent multiplier, and the chart, updates instantly.

What Actually Counts as Net Operating Income

Getting NOI right matters more than almost anything else in this calculation, since even a small mistake here throws off your cap rate. NOI includes all the income a property generates, rent plus extras like parking or storage fees, minus vacancy loss and every operating expense needed to run the property day to day. That means property taxes, insurance, repairs and maintenance, property management fees, utilities you pay as the owner, and landscaping or HOA dues all count.

What does not belong in NOI is just as important. Your mortgage payment, whether principal or interest, never gets subtracted here, because cap rate is meant to measure the property's performance independent of how it's financed. Capital expenditures, like a new roof or a full renovation, are also usually excluded, along with depreciation, since that's an accounting concept rather than actual cash leaving the property. Keeping these separate is exactly why we built the breakdown mode into the calculator, so you can see clearly which numbers belong where.

What's a Good Cap Rate? It Depends on the Property

There's no single number that counts as a "good" cap rate everywhere, because cap rate reflects risk as much as return. A low cap rate, say 4%, usually means investors see the property as low risk, often because it sits in a strong, stable market or comes with high-quality tenants on long leases. A higher cap rate, say 8% or more, usually signals more risk, whether that's an older building, a weaker location, shorter leases, or more management headaches.

The table above this calculator shows typical ranges by property type, from stable Class A multifamily buildings in the 4% to 5.5% range, up to hotels and hospitality assets that often run 7% to 10% because of how much their income can swing. Use these ranges as a sanity check for whatever your calculator result comes back with, not as a hard rule, since local market conditions and interest rates shift these ranges over time.

Using the Reverse Valuation: What Should You Actually Pay?

One of the most useful things you can do with this calculator isn't just checking a cap rate, it's flipping the formula around. Enter your target cap rate, the return you personally want from a deal, and the calculator tells you the maximum price you should pay for that NOI to hit your goal. If a seller is asking more than that number, you know upfront that you're either accepting a lower return or you need to negotiate the price down.

This reverse valuation is especially handy when you're comparing multiple listings at once. Instead of calculating each property's cap rate separately and trying to compare them mentally, set your target cap rate once and see instantly which asking prices line up with your goals and which ones don't.

Gross Rent Multiplier: A Quick Second Opinion

Alongside cap rate, the calculator also shows your gross rent multiplier, or GRM, which is simply the property value divided by its gross annual rental income. A lower GRM generally means a better deal relative to rent, similar in spirit to a lower price-to-earnings ratio for a stock. GRM is rougher than cap rate since it ignores expenses entirely, but it's a fast way to sanity-check a deal before you dig into the full expense breakdown, and useful for comparing properties where expense data isn't available yet.

Cap Rate vs Cash-on-Cash Return: Two Different Questions

Cap rate tells you how the property performs as an asset, independent of financing. Cash-on-cash return tells you how your actual cash performs once a mortgage enters the picture. Turn on the advanced financing section, add your down payment percentage, loan rate, and term, and the calculator works out your annual mortgage payment, your cash flow after debt, and your cash-on-cash return automatically.

These two numbers can tell very different stories on the same property. A deal with a modest 6% cap rate can still deliver a strong double-digit cash-on-cash return if you use leverage well, because you're only putting a fraction of the purchase price down while collecting the full NOI. On the flip side, a high cap rate property can turn cash-flow negative if the loan rate is high enough that debt payments eat into the NOI faster than the return justifies. The DSCR, or debt service coverage ratio, shown alongside cash-on-cash return tells you how comfortably the NOI covers your loan payment. Above 1.2 is generally considered healthy by most commercial lenders, while anything under 1.0 means the property isn't generating enough income to cover its own debt.

Common Mistakes People Make With Cap Rate

The single biggest mistake is using a seller's advertised NOI without checking it. Listing agents sometimes present optimistic numbers, skip a vacancy allowance, or leave out a real expense like management fees, which inflates the cap rate on paper. Always rebuild NOI yourself using the breakdown mode here so you know exactly what's assumed.

Another common error is treating cap rate as a complete investment decision on its own. It says nothing about appreciation potential, tax benefits, financing terms, or how much work a property will need. It's a screening tool, a fast first filter, not the final word. Pair it with cash-on-cash return, a look at the local market, and your own goals before committing to any deal.

How Rising or Falling Interest Rates Move Cap Rates

Cap rates don't move in a vacuum. When interest rates rise, borrowing gets more expensive, which cools buyer demand and often pushes purchase prices down relative to income, and cap rates up, since the same NOI now buys more return at a lower price. When rates fall, the opposite tends to happen, cheaper financing draws in more buyers, prices climb, and cap rates compress.

This is why comparing a cap rate from a few years ago to today's market without adjusting for the interest rate environment can be misleading. A 6% cap rate that looked average during a low-rate period might look excellent once rates have climbed, simply because the whole market has repriced around it. Keep half an eye on where rates are heading when you're deciding whether a cap rate looks attractive or not.

Cap Rate Isn't the Whole Story: Appreciation and Upside

A property with a lower cap rate today can still be a smart buy if you expect strong appreciation, rising rents, or a value-add opportunity like renovating outdated units to raise NOI over time. Cap rate is a snapshot of current income against current price, it says nothing about where either of those numbers might be headed.

This cuts both ways. A property with an unusually high cap rate might be pricing in real problems, deferred maintenance, a struggling local economy, or difficult tenants, rather than simply being a bargain. Always ask why a cap rate looks the way it does before treating a higher number as automatically the better deal.

Comparing Multiple Properties With Cap Rate

Cap rate really shines when you're weighing several listings against each other. Run each property's NOI and asking price through the calculator, and you get a clean, standardized percentage for every one of them, no matter how different their financing, size, or location might be. This lets you rank a whole shortlist quickly before spending time on deeper due diligence.

Just make sure you're building each NOI the same way. If one seller's number already assumes a low vacancy rate and another doesn't, your comparison won't be fair. Use the breakdown mode with your own consistent vacancy and expense assumptions across every property you're comparing, so the cap rates you end up with are actually apples to apples.

A Simple Worked Example

Say you're looking at a small apartment building listed at 500,000 dollars. The listing shows gross rental income of 54,000 dollars a year, plus 1,200 dollars from coin-op laundry. You expect a realistic 5% vacancy and credit loss, and you estimate annual operating expenses, taxes, insurance, repairs, and management, at 18,500 dollars.

Run those numbers through the breakdown mode and you'll land on an NOI in the mid-30,000s, which at the 500,000 dollar asking price works out to a cap rate right around 7%, solidly in range for a Class B or C multifamily property. If you want a personal target of 8%, the reverse valuation shows the maximum you should really be paying for that same income stream, giving you a solid, evidence-based number to bring into any negotiation.