Free calculator · Real Estate
NOI, OER & Cap Rate
Calculates net operating income, the operating expense ratio, and the implied cap rate for an income property. Inputs are effective gross income, a line-item operating expense budget, and a purchase price or value.
By Devon Coombs, CPA, MBA · Teaching Professor of Finance, Santa Clara University · Reviewed August 2026
From the author: Devon Coombs, CPA, MBA teaches finance at Santa Clara University and works with corporate teams on practical AI.
AI training for finance teams · Consulting · The 10 Laws of Finance
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NOI, OER & Cap Rate Calculator
Inputs
EGI → NOI
Effective Gross Income
$2,209,500
Property taxes
−$275,000
Insurance
−$81,600
Management fee
5.0% of EGI
−$110,475
Repairs & maintenance
−$100,000
Utilities (landlord)
−$72,000
Administrative
−$42,000
Other
−$30,000
Net Operating Income
$1,498,425
Operating Exp. Ratio
32.2%
$711,075 opex
NOI
$1,498,425
before debt & capex
Going-in Cap Rate
5.99%
NOI ÷ $25,000,000
Learn the concept
This calculator comes from the free Real Estate Finance course, where the concept is taught with readings, worked examples, and practice questions.
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Built by Devon Coombs, CPA, MBA, Teaching Professor of Finance at Santa Clara University.