Rental Property Calculator: Cash Flow, Cap Rate & Cash-on-Cash
Run the numbers on a rental before you buy it — or before you decide to rent out the home you already own.
Purchase & financing
Income & expenses
Estimates for planning only — not a loan offer, appraisal or tax advice. Results depend on the numbers you enter.
The metrics, explained
| Metric | Formula | What it tells you |
|---|---|---|
| Net operating income (NOI) | Rent − vacancy − operating expenses (excludes mortgage) | The property’s earning power |
| Cap rate | NOI ÷ price | Return if bought with cash; compare across properties |
| Cash flow | NOI − mortgage payment | What lands in your account monthly |
| Cash-on-cash | Annual cash flow ÷ cash invested | Return on your actual dollars |
| DSCR | NOI ÷ debt service | Safety margin lenders look at |
Don’t skip the “invisible” expenses
New landlords underestimate vacancy, maintenance and capital expenditures (roof, HVAC, water heater). Budgeting a percentage of rent for each smooths out the big hits. Self-managing? Keep management at 0% but value your time honestly.
Renting out your current home?
Use your home’s current value as the price and your existing loan terms. Then follow the landlord playbook, price the rent correctly, and screen tenants legally. When you’re ready, list your rental free.
FAQ
What is a good cap rate?
There's no universal number. Cap rates vary by market, property type and risk. Compare against similar local properties rather than a national rule of thumb.
What is DSCR and why do lenders care?
Debt service coverage ratio is net operating income divided by mortgage payments. Above 1.0 means the property's income covers the loan; many investor loans look for roughly 1.2 or higher.
Is the 1% rule reliable?
It's a quick screen (monthly rent at least 1% of price), not an investment decision. In many higher-cost markets few properties meet it, and plenty that do have high expenses. Always run full numbers.
Keep crunching the numbers
Commission Savings Calculator
See exactly how much you keep by selling by owner vs. a traditional listing.
Seller Net Proceeds Calculator
Estimate the cash you walk away with after payoff, closing costs and concessions.
Mortgage Calculator
Monthly payment with taxes, insurance, HOA and PMI — plus a full amortization schedule.
Home Affordability Calculator
How much house your income supports using lender-style 28/36 debt ratios.
Rent vs. Buy Calculator
Compare the true cost of renting and buying over the years you plan to stay.
Closing Cost Estimator
Line-by-line closing cost estimate for buyers and sellers.
Sell-By-Owner Readiness Quiz
8 questions that tell you whether FSBO, flat-fee MLS or an agent fits you best.