Net Operating Income (NOI) Calculator

What net operating income tells you

Net operating income is the single most important number in income-based real estate. It captures what a property earns from its own operations — all rental and ancillary income, less the costs of running it — before a single rupee of mortgage or income tax is considered. Collect ₹7,20,000 in annual rent, spend ₹2,40,000 on tax, insurance, maintenance and management, and the property produces an NOI of ₹4,80,000. That figure, not the headline rent, is what investors, lenders and appraisers actually build on.

Why NOI deliberately ignores your loan

The defining feature of NOI is what it leaves out. It excludes mortgage payments, debt service and income tax entirely. This is not an oversight — it is the whole point. Financing and tax depend on the individual buyer: how much they borrowed, at what rate, and their personal tax position. By stripping those out, NOI isolates the property’s intrinsic earning power, so two investors eyeing the same building — one paying cash, one borrowing 80% — see the identical NOI. The impact of their loans shows up later, in cash-flow and cash-on-cash analysis, not here.

The engine of valuation

NOI’s biggest job is valuation. Divide it by a market cap rate and you get an estimate of what the property is worth. If comparable assets trade at a 6% cap rate and your property earns ₹4,80,000 in NOI, its implied value is roughly ₹80,00,000. Because value moves directly with NOI at a given cap rate, every rupee you add to NOI — by lifting rent, adding parking income or trimming expenses — increases the property’s worth. This is why experienced investors obsess over growing NOI rather than just collecting rent.

Getting NOI right

An NOI is only as honest as its inputs. The most common error is assuming full occupancy; deducting a realistic vacancy and collection allowance of a few percent gives a far truer figure. Equally important is what you keep *out* of operating expenses: capital expenditure like replacing a roof, along with loan payments and income tax, do not belong there. Include every income stream — rent, parking, signage, amenity fees — so nothing is missed. Review NOI at least yearly, because as rents rise and costs shift, the number moves, and with it the value of your investment.