Turn rent, reserves, operating costs, and debt service into a fast rental-property screen. See monthly cash flow, annual NOI, cap rate, and the rent needed to break even—without a spreadsheet.
What you'll calculate
The core operating metrics investors use for an initial rental screen.
Cash flow
After reserves and debt
Annual NOI
Before mortgage payment
Cap rate
On all-in basis
Break-even rent
For your cost stack
Jump to
Start with the rent and payment you expect, then add conservative operating reserves. Results update instantly and remain on your device.
Use conservative income and reserve assumptions to screen a rental in under a minute. Results update locally as you type.
Include principal and interest only if taxes and insurance are entered below.
Owner-paid utilities, lawn care, or other recurring costs.
Purchase price plus closing costs and any upfront repairs used for your cap-rate basis.
Cash flow and cap rate are screening estimates, not a property valuation or investment recommendation. Confirm rent, taxes, insurance, repairs, and financing before making an offer.
Rental cash-flow snapshot
Results are after operating reserves and debt service.
Monthly cash flow
-$7
-$84 per year after debt service.
Before mortgage debt service.
Annual NOI divided by your all-in basis.
Rent needed to cover all listed monthly costs and debt service.
Monthly operating-cost snapshot
Free and private: all calculations run locally in your browser. No signup or property data is required.
Start with income, subtract realistic operating expenses to get net operating income, then subtract the mortgage payment to see cash flow. Keeping those steps distinct makes it easier to compare properties and spot assumptions that need a second look.
Vacancy, maintenance, and management costs are often ignored in quick deal math. Add rates that fit the property and market rather than relying on rent alone.
NOI is income after operating costs but before mortgage debt service. It is the numerator used for the cap-rate calculation in this tool.
Confirm taxes and insurance, compare rent with current listings and leases, and consider a weaker-rent or longer-vacancy scenario before you commit capital.
Formula used
Monthly cash flow = monthly rent − operating reserves and costs − mortgage payment. Cap rate = annual NOI ÷ purchase or all-in basis.
This tool starts with monthly rent, subtracts vacancy, maintenance, management, property taxes, insurance, HOA dues, and other recurring operating costs to calculate monthly NOI. It then subtracts the monthly mortgage payment to show monthly and annual cash flow.
Net operating income (NOI) is rental income less operating expenses, before mortgage debt service. Here, that includes vacancy, maintenance, management, taxes, insurance, HOA dues, and other entered operating costs. Your exact expense categories can vary by property and market.
Cap rate is annual NOI divided by the purchase or all-in basis you enter. Because it is calculated before mortgage payments, cap rate gives you a financing-independent way to compare the operating performance of potential rentals.
No. Break-even rent is the rent needed to cover the costs you entered, including debt service. It does not predict what a tenant will pay. Verify projected rent with comparable leases, local demand, condition, and a qualified local professional before relying on it.
