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

What You'll Need to Calculate Cap Rate

• Property Purchase Price (or current market value)
• Gross Annual Rental Income — total rent collected per year
• Operating Expenses — property taxes, insurance, maintenance, property management, utilities, HOA fees, vacancy allowance, and any other costs
• Calculator or spreadsheet (optional — the Cap Rate Calculator does it instantly)

Step-by-Step Guide: How to Calculate Cap Rate by Hand

Calculating cap rate manually helps you understand exactly where your returns come from. The formula is simple: Cap Rate = (Net Operating Income ÷ Property Value) × 100. But you need two key numbers — Property Value and Net Operating Income (NOI). Let's break it down into six steps.

1. Determine Property Value. Use the purchase price if you're buying, or an appraised current market value. For example, $500,000.
2. Calculate Gross Annual Rental Income. Sum all rent collected over 12 months. If you have multiple units, add them. If there is a vacancy rate, adjust below.
3. Calculate Operating Expenses. Add up all annual costs: property taxes, insurance, maintenance, property management fees, utilities you pay, HOA dues, and other expenses. Remember to account for a vacancy rate (e.g., 5% of gross income).
4. Compute Net Operating Income (NOI). Subtract total operating expenses from gross rental income: NOI = Gross Income - Operating Expenses. If you included vacancy, it's already accounted for.
5. Apply the Cap Rate Formula. Divide NOI by Property Value, then multiply by 100: Cap Rate = (NOI ÷ Property Value) × 100. The result is a percentage.
6. Interpret Your Result. Compare the cap rate to market averages. Cap rate ranges typically fall between 4% and 12%, with lower rates indicating lower risk and higher rates potentially higher returns.

Worked Example 1: Single-Family Rental

Property Value: $250,000
Gross Annual Rent: $30,000
Operating Expenses:

• Property taxes: $3,000
• Insurance: $1,200
• Maintenance: $2,500
• Property management (8% of rent): $2,400
• Vacancy allowance (5%): $1,500
• Other (HOA, utilities): $900

Total Operating Expenses: $11,500
NOI: $30,000 - $11,500 = $18,500
Cap Rate: ($18,500 ÷ $250,000) × 100 = 7.4%

This 7.4% cap rate suggests a moderate return — typical for a single-family home in an average location. For a full breakdown of what this means, see our What Is Cap Rate guide.

Worked Example 2: Small Multi-Family (4 Units)

Property Value: $600,000
Gross Annual Rent: $72,000 ($1,500/unit × 4 × 12)
Operating Expenses:

• Property taxes: $7,200
• Insurance: $2,800
• Maintenance: $4,000
• Property management (10% of rent): $7,200
• Vacancy allowance (6%): $4,320
• Utilities (owner-paid): $2,400
• Other (landscaping, repairs): $1,200

Total Operating Expenses: $29,120
NOI: $72,000 - $29,120 = $42,880
Cap Rate: ($42,880 ÷ $600,000) × 100 = 7.15%

This cap rate is close to the single-family example because the higher income is offset by higher expenses. Always use the actual formula — guessing can cost you. For the precise equation, check the Cap Rate Formula page.

Common Pitfalls When Calculating Cap Rate

• Forgetting vacancy costs. A 5–10% vacancy allowance is realistic; ignoring it overstates NOI.
• Using gross income instead of NOI. Cap rate is based on net income after expenses, not gross rent.
• Mixing up monthly and annual numbers. Always use annual figures. Multiply monthly rent by 12.
• Including mortgage payments. Debt servicing is not an operating expense — cap rate measures property performance, not financing.
• Using the wrong property value. Use current market value or purchase price, not future projections.

Once you master the manual calculation, use our Cap Rate Calculator for quick, error-free results. For more context, read our Cap Rate FAQs.