AbraCalc

Net Operating Income (NOI) Calculator

Calculate Net Operating Income (NOI) for a rental property: gross rental income minus vacancy and operating expenses.

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How to use this tool

  1. Enter gross annual rent, vacancy rate and annual operating expenses in the fields above.
  2. Results update instantly as you type — or click Calculate.
  3. Read your net operating income (noi) and the full breakdown beneath it.

NOI is the foundation of commercial real estate valuation. It feeds directly into cap rate and DSCR calculations, making it essential for every investment analysis.

Formula

Effective Gross Income (EGI) = Gross Annual Rent × (1 − Vacancy Rate ÷ 100)

Net Operating Income (NOI) = EGI − Annual Operating Expenses

Expense Ratio (%) = Operating Expenses ÷ EGI × 100

How it works

This calculator works down a standard property income statement: it first deducts a vacancy allowance from gross rent to arrive at the income actually collected (effective gross income), then subtracts all operating costs — maintenance, insurance, property management, taxes — to reach NOI, the fundamental measure of a rental property's operating profitability.

The expense ratio shows what proportion of collected income is consumed by running costs; a ratio above 50 % is generally considered high for residential property. Debt service (mortgage payments) is excluded from NOI by convention, making it independent of financing structure.

Worked example

Worked example

  1. Gross annual rent: $24,000; vacancy rate: 5%; annual operating expenses: $6,000.
  2. Vacancy loss = $24,000 × 0.05 = $1,200.
  3. Effective Gross Income = $24,000 − $1,200 = $22,800.
  4. NOI = $22,800 − $6,000 = $16,800.
  5. Expense Ratio = $6,000 ÷ $22,800 × 100 ≈ 26.32%.

Effective Gross Income = $22,800; NOI = $16,800; Expense Ratio = 26.32%

Key terms

Gross rental income
The total rent a property would generate if 100% occupied for the full year, before any vacancy or expense deductions.
Vacancy rate
The percentage of the year the property is expected to be unoccupied or generate no rent; typically 5–10% for residential property.
Effective Gross Income (EGI)
Gross rent minus the expected vacancy loss — the income a landlord can realistically plan to collect.
Operating expenses
Recurring costs of running the property: property tax, insurance, maintenance, management fees, and utilities paid by the owner. Excludes mortgage payments and capital expenditure.
Expense ratio
Operating expenses expressed as a percentage of effective gross income; a key indicator of how efficiently a property is being managed.

Frequently asked questions

What expenses are NOT included in NOI?
NOI excludes mortgage principal and interest, income taxes, depreciation, and capital expenditures (major repairs). It includes property taxes, insurance, maintenance, management fees, and utilities paid by the landlord.
What is the 50% rule?
The 50% rule is a quick estimate that operating expenses (excluding mortgage) will equal roughly 50% of gross rent. NOI ≈ gross rent × 50%. It's a rough screen, not a substitute for actual expense analysis.

References & sources