Net Operating Income Calculator

Estimate net operating income by subtracting vacancy loss and property operating expenses from gross income. This page also keeps the formula, examples, FAQs, and references close by so you can check the result with confidence.

What This Net Operating Income Calculator Helps You Do

NOI = effective gross income - operating expenses. Review the formula and examples below if you want to see how the result is derived.

This page is meant to give you a fast answer, but it also helps you double-check the math before you make a decision. Start with the inputs that you already know, run the calculation, and then compare the output with the formula, examples, and FAQs below so you can see whether the answer fits the situation you are modeling.

If the result looks off, the usual causes are a unit mismatch, a missing decimal, the wrong scenario, or a value that needs to be entered as a rate instead of a total. The notes on this page are designed to make those checks easy without forcing you to leave the calculator and search for context elsewhere.

  • Use the calculator first for a quick estimate.
  • Use the formula to understand how the result is built.
  • Use the examples to compare common use cases.
  • Use the references when the answer depends on a standard or assumption.

Common Checks

A quick result is useful, but the best result is one that still makes sense when you look at it a second time. If you are comparing scenarios, try changing one input at a time so you can see which variable has the biggest impact on the final answer. That makes it much easier to spot whether the calculation matches your expectations.

It also helps to keep the context of the problem in mind. A calculator can tell you the math, but you still need to decide whether the input represents a total, a rate, an average, or a category-specific assumption. When in doubt, start with a simple example from the page and scale up from there.

  • Check that every unit matches the rest of the problem.
  • Keep rates, totals, and averages separate.
  • Adjust one variable at a time when testing scenarios.
  • Use the smallest realistic input first, then scale upward.

Scenario Planning

This calculator is especially useful when you want a quick answer before you commit time, money, or effort. Try one baseline input set, then change a single number and compare the result so you can see how sensitive the answer is to that variable.

That makes the page useful for more than just arithmetic. It becomes a small decision aid that helps you compare options, test assumptions, and explain the final number with confidence when you need to share it with someone else.

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Result

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Quick Answer: NOI = effective gross income - operating expenses. Review the formula and examples below if you want to see how the result is derived.

How to Calculate Net Operating Income Calculator

  1. Calculate potential gross income: Multiply rentable area by rent per square foot and add other income.
  2. Subtract vacancy loss: Reduce the total by the portion of space not occupied.
  3. Subtract operating expenses: Deduct property tax, insurance, maintenance, and other operating costs.

Net Operating Income Calculator Formula

Net operating income = effective gross income - operating expenses
Variable Meaning Unit
Effective gross income Potential gross income after vacancy loss $
Operating expenses Property taxes, insurance, maintenance, utilities, and similar costs $

Worked Examples

USA - Office building
  • Rentable area: 1,500 sq ft
  • Rent per sq ft: $300
  • Other income: $2,000
  • Occupancy rate: 85%
  • Property tax: $35,000
  • Management fees: $22,000
  • Insurance: $10,000
  • Maintenance: $18,000
  • Utilities: $15,000
  • Advertising: $5,000
  • Repairs: $7,000

Result: $271,500

This matches a simple property NOI calculation used in real estate analysis.

UK - Retail strip
  • Rentable area: 3,000 sq ft
  • Rent per sq ft: $180
  • Other income: $5,000
  • Occupancy rate: 92%
  • Property tax: $18,000
  • Management fees: $14,000
  • Insurance: $6,000
  • Maintenance: $12,000
  • Utilities: $8,000
  • Advertising: $3,000
  • Repairs: $4,000

Result: Positive NOI

Higher occupancy improves effective gross income and lifts NOI.

EU - Apartment block
  • Rentable area: 10,000 sq ft
  • Rent per sq ft: $55
  • Other income: $12,000
  • Occupancy rate: 95%
  • Property tax: $40,000
  • Management fees: $30,000
  • Insurance: $15,000
  • Maintenance: $20,000
  • Utilities: $16,000
  • Advertising: $4,000
  • Repairs: $9,000

Result: Strong NOI

NOI focuses on recurring property operations, not financing costs.

How to Interpret Your Results

Range Meaning Action
Higher NOI The property generates more operating income after expenses Compare against purchase price or cap rate.
Typical NOI The property is operating at a normal income level Use it to benchmark similar properties.
Lower NOI Vacancy or expenses are weighing on income Review rent, occupancy, and operating cost controls.

Frequently Asked Questions

NOI is the income from a property after operating expenses but before financing costs and taxes.

No. Debt service is not part of NOI.

Vacancy lowers effective gross income and should be included in a realistic estimate.
Planning note: NOI is a property operating metric and excludes financing costs, taxes, and capital expenditures.

References

Last reviewed: April 2026