Rental Property Calculator
Enter a property's price, financing, rent, and expenses to estimate monthly cash flow, cap rate, cash-on-cash return, NOI, and DSCR. Everything runs in your browser. Nothing you type is sent anywhere or saved.
Property details
Results
| Gross scheduled income | $0 |
|---|---|
| Less vacancy | $0 |
| Effective gross income | $0 |
| Less operating expenses | $0 |
| Net operating income (NOI) | $0 |
| Less mortgage (P&I) | $0 |
| Monthly cash flow | $0 |
GRM: – · Operating expense ratio: –. These are estimates, not a promise of returns.
How this rental property calculator works
Every number on the right comes from a standard real estate formula. Here's exactly what the tool does with your inputs, so you can check the math yourself.
Net operating income (NOI)
NOI is your income after operating costs but before the mortgage. The calculator starts with gross rent plus any other income, subtracts a vacancy allowance to get effective gross income, then subtracts operating expenses (taxes, insurance, management, a maintenance and capital-expenditure reserve, and anything you add). Debt payments, depreciation, and one-time capital projects are deliberately left out of NOI.
Cap rate
Cap rate = annual NOI ÷ purchase price, shown as a percentage. It tells you the property's unleveraged yield, which makes it handy for comparing two properties regardless of how each is financed.
Cash-on-cash return
Cash-on-cash return = annual pre-tax cash flow ÷ total cash invested. Pre-tax cash flow is NOI minus your annual mortgage payments. Total cash invested is your down payment plus closing costs plus any upfront rehab. Unlike cap rate, this figure reflects your financing, so it shows what your actual out-of-pocket dollars earn in year one.
DSCR
Debt service coverage ratio = annual NOI ÷ annual debt service. Lenders use it to size loans; many commercial and DSCR-loan programs look for roughly 1.25 or higher. A DSCR below 1.0 means the property doesn't cover its own mortgage from operations. If you buy all cash, there's no debt service, so DSCR doesn't apply.
The quick screens
The 1% rule flags whether monthly rent is at least 1% of the purchase price, a fast first-glance filter that has gotten much harder to hit in recent years. Gross rent multiplier (price ÷ annual gross rent) is another shorthand. Treat both as screens for a closer look, not as buy signals on their own.
Common questions
What's a good cash-on-cash return on a rental?
There's no universal cutoff, and it depends on your market and goals. Many investors treat something in the high single digits to low double digits as solid for a stabilized long-term rental, but a lower return can still make sense if you're buying for appreciation or a specific tax situation. Use the number to compare deals against each other, not against a magic threshold.
Why is my cap rate different from my cash-on-cash return?
Cap rate ignores your loan entirely, so it measures the property. Cash-on-cash includes your mortgage and your actual cash in the deal, so it measures your return. With leverage they'll usually differ, sometimes by a lot.
Should maintenance and capex really come out of NOI?
Yes. Reserving for repairs and eventual big replacements (roof, HVAC, water heater) is a real operating cost even in months you don't spend it. Leaving it out inflates NOI and every metric built on it. The default reserve here is a starting point; adjust it for the age and condition of the property.
Does this calculator store or send my numbers?
No. The math runs entirely in your browser with JavaScript. Nothing you enter is transmitted to a server or saved between visits.