Real Estate Tools

Real Estate Cap Rate & Cash-on-Cash Calculator

Turn a rental property's numbers into NOI, cap rate, and financed cash-on-cash return.

Enter a property's purchase price, income, operating expenses, and financing terms to see net operating income (NOI), capitalization rate, and cash-on-cash return, calculated the same way Swoopr's Real Estate & REIT Investing hub defines them.

By Swoopr Editorial Team

Published · Updated

AI-assisted content · Swoopr Investment is responsible for the final published article.

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Direct Answer

Net operating income (NOI) is gross property income minus operating expenses, excluding debt service and capital expenditures. Cap rate is NOI divided by property value. Cash-on-cash return is annual pre-tax cash flow (NOI minus annual mortgage debt service) divided by total cash invested (down payment plus closing and upfront repair costs).

These are the same definitions Swoopr's Real Estate & REIT Investing hub and its NOI and cap rate explainers use, so the numbers below stay consistent with the rest of Swoopr's real-estate education.

Cap Rate & Cash-on-Cash Calculator

Results are mathematical estimates based on the numbers you enter. Not investment advice. All calculation happens locally in your browser; nothing is sent to a server.

Property & Income
What you're paying (or plan to pay) for the property. Must be greater than 0.
Use this to compute cap rate against an appraised or estimated value that differs from the purchase price. Leave blank to use the purchase price.
Total rent collected over a year, before any expenses.
Any other annual property income beyond rent.
Property taxes, insurance, maintenance, management, utilities, and vacancy loss. Excludes mortgage principal, interest, and capital expenditures.
Financing (for cash-on-cash return)
Between 0 and 100. Enter 100 for an all-cash purchase (no loan, no debt service).
Annual mortgage interest rate. Enter 0 for a 0% loan. Ignored when down payment is 100%.
Length of a standard fully-amortizing loan, in years.
Upfront closing costs, added to total cash invested.
Any upfront repair or rehab spend before renting, added to total cash invested.

Methodology

The calculator applies the formulas below directly to your inputs:

NOI = Gross income − Operating expenses
Cap Rate = NOI ÷ Property value
Annual debt service = Standard fixed-rate mortgage payment × 12
Annual pre-tax cash flow = NOI − Annual debt service
Cash-on-Cash Return = Annual pre-tax cash flow ÷ Total cash invested

Assumptions and limitations

FAQ

What is net operating income (NOI)?

Net operating income (NOI) is a property-level measure of income after operating expenses but before financing costs and capital expenditures. NOI = Gross property income − Operating expenses. It excludes debt service (mortgage principal and interest) and capex, which are layered on separately when evaluating financed returns.

How is cap rate calculated?

Capitalization rate (cap rate) relates a property's income to its value: Cap Rate = NOI ÷ Property value. It is a financing-agnostic measure, unaffected by how the property is paid for, and is most useful for comparing similar properties or tracking a single property's income yield over time.

What is cash-on-cash return?

Cash-on-cash return measures annual pre-tax cash flow relative to the actual cash invested: Cash-on-Cash Return = Annual pre-tax cash flow ÷ Total cash invested. Annual pre-tax cash flow is NOI minus annual mortgage debt service. Unlike cap rate, cash-on-cash return depends on financing terms, so two investors buying the same property with different down payments and loan terms get different cash-on-cash returns.

Why does the mortgage payment affect cash-on-cash return but not NOI?

NOI is designed to measure a property's income-producing ability independent of how it is financed, so debt service is deliberately excluded from it. Cash-on-cash return, by contrast, measures the return on the investor's actual out-of-pocket cash, so the mortgage payment is subtracted from NOI as a cash outflow at that later step, not folded into NOI itself.