What Is a Cap Rate? Definition, Formula, and How to Calculate It

Cap rate is one of the first numbers real estate investors calculate when evaluating a rental property, and for good reason. It condenses a property's income and value into a single percentage, making it possible to compare very different properties side by side. Here's what a cap rate is, how to calculate it, and how to use it alongside other metrics when underwriting a deal.

Cap Rate Definition

A cap rate, short for capitalization rate, is the ratio of a property's net operating income (NOI) to its current market value or purchase price, expressed as a percentage. According to J.P. Morgan, cap rate represents the annualized return an investor would expect to receive if they purchased the property outright, in cash, based on its income alone.

Cap rate is a snapshot of income relative to price. It doesn't account for financing, so it's the same whether you're paying cash or using a loan. That's exactly why it's useful as a comparison tool: it strips financing out of the equation so you can compare the underlying performance of different properties on equal footing.

The Cap Rate Formula

The cap rate formula is straightforward:

Cap Rate = (Net Operating Income ÷ Property Value) × 100

Net operating income (NOI) is the property's annual income after operating expenses, but before mortgage payments, income taxes, and depreciation. Property value is either the purchase price or current market value, depending on whether you're evaluating a potential purchase or an existing asset.

The same formula can be rearranged to solve for other variables:

To estimate value: Property Value = NOI ÷ Cap Rate

To estimate NOI: NOI = Property Value × Cap Rate

This flexibility is what makes cap rate useful beyond a simple percentage. If you know the market cap rate for a property type in a given area, you can estimate what a property should be worth based on its income, or estimate the income a property would need to produce to justify its asking price.

How to Calculate Cap Rate: Step-by-Step Example

Here's a simple walkthrough you can use as a manual cap rate calculator for any rental property.

Step 1: Calculate gross annual rental income. Add up the total rent the property is expected to collect over a year. For example, a property renting for $2,500 per month generates $30,000 in gross annual income.

Step 2: Subtract operating expenses. Operating expenses include property taxes, insurance, maintenance, property management, and vacancy reserves, but not mortgage payments. If annual operating expenses total $9,000, the property's NOI is $30,000 − $9,000 = $21,000.

Step 3: Divide NOI by property value. If the property is valued at $300,000, the calculation is:

$21,000 ÷ $300,000 = 0.07, or a 7% cap rate.

Step 4: Compare against market benchmarks. Once you have the cap rate, compare it to typical cap rates for similar properties in the same market to gauge whether the deal is priced attractively relative to its income.

What's a Good Cap Rate for Rental Property?

"Good" is relative to market, property type, and risk tolerance, but general benchmarks provide a useful starting point. For long-term residential rentals, a cap rate in the 5% to 8% range is generally considered solid in most markets, with many investors targeting the 5% to 7% range as a balance between cash flow and appreciation potential, according to Rentana's 2026 market analysis. Multifamily cap rates in 2026 have averaged around 5.6% across all property classes, though they vary significantly: higher-quality assets in strong markets tend to trade at lower cap rates (reflecting lower risk and more stable income), while older or higher-risk properties in secondary and tertiary markets often carry higher cap rates.

A higher cap rate isn't automatically better. It usually signals higher potential return, but also higher perceived risk, whether from the property's condition, the market's stability, or tenant quality. A lower cap rate often reflects a more stable, lower-risk asset in a stronger market, where investors accept lower current income in exchange for more predictable performance and potential appreciation.

Factors That Affect Cap Rate

Several variables move cap rates up or down for a given property:

• Location: Cap rates are typically lower in high-demand metro areas and higher in secondary or tertiary markets, reflecting differences in perceived risk and growth potential.

• Property condition and age: Newer, well-maintained properties tend to command lower cap rates because they carry less near-term capital expenditure risk.

• Property class and tenant quality: Class A properties with strong tenants generally trade at lower cap rates than Class B or C properties.

• Market interest rates: As borrowing costs rise, cap rates often rise as well, since investors require higher income relative to price to offset higher financing costs.

• Local rental demand: Markets with tight vacancy and strong rent growth can support lower cap rates because income is more predictable.

Cap Rate vs. DSCR: What's the Difference?

Cap rate and debt service coverage ratio (DSCR) are related but answer different questions. Cap rate measures a property's income relative to its value, which helps investors compare deals and estimate profitability independent of financing. DSCR measures a property's income relative to its mortgage payment, which lenders use to determine whether the property qualifies for financing.

In practice, many investors use cap rate to screen potential deals first, then confirm the property can support financing by calculating its DSCR against a specific loan structure. A property with an attractive cap rate can still fail to meet a lender's minimum DSCR if the purchase price, down payment, and loan terms don't line up. You can learn more about how DSCR qualification works in Dominion Financial's rental property financing guide.

Limitations of Cap Rate

Cap rate is a useful screening tool, but it has limits. It doesn't account for financing costs, so two investors buying the same property with different loan terms will have very different actual cash flow, even though the cap rate is identical. It also relies on accurate NOI figures, and inflated income or underestimated expenses can make a property look more attractive than it actually is. Because of this, experienced investors treat cap rate as a starting point for comparison, not a final answer, and pair it with a full cash flow and DSCR analysis before making an offer.

The Bottom Line

Cap rate gives real estate investors a fast, standardized way to evaluate a rental property's income relative to its price. Calculating it is simple: divide net operating income by property value. Interpreting it well takes more context, since the right cap rate depends on the market, property type, and your investment goals. Once a property's cap rate looks attractive, the next step is confirming it can support financing, which is where DSCR and full cash flow analysis come in.

If you've identified a rental property with a cap rate that works for your strategy, Dominion Financial's DSCR loan programs can help you move forward with financing based on the property's rental income.

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