Analyze rental property investments with IRR, cap rate, cash flow, and full breakdown over time.
This tool is built for buy-and-hold investors sizing up a single-family home, duplex, or small multifamily property in the US. You enter the purchase price, down payment, interest rate, monthly rent, and recurring expenses, and it returns your monthly cash flow, cap rate, and cash-on-cash return in one view. Unlike a basic mortgage tool that stops at the payment, this calculator layers in vacancy, property management, maintenance, taxes, and insurance — the costs that decide whether a rental is profitable. It's an investment-analysis tool, not a homebuyer's tool, so the focus is return on capital rather than affordability. If you're analyzing your own residence instead, the math is entirely different. Use this when you're comparing deals, screening listings, or stress-testing a property before you make an offer.
Running a deal takes a couple of minutes once you have the listing details. Work through these steps:
Enter the purchase price and down payment.
A typical investment loan needs 20–25% down, so for a $300,000 property expect $60,000–$75,000 up front.
Add your loan terms.
Input the interest rate and term. Investment-property rates run higher than owner-occupied, around 7–8% in 2026.
Input expected monthly rent.
Use realistic local comps, not the seller's optimistic projection.
Fill in operating expenses.
Include property tax, insurance, management (often 8–10% of rent), maintenance, and a vacancy allowance of 5–8%.
Review your results.
The calculator shows monthly cash flow, cap rate, and cash-on-cash return.
Test different scenarios.
Lower the rent or raise the vacancy rate to see how fragile the cash flow is before you commit.
Save the numbers for each property so you can compare deals side by side.
Three formulas do the heavy lifting, and none of them require a finance degree. First, net operating income (NOI) is your annual rent minus all operating expenses, but before the mortgage:
NOI = Annual Rental Income − Operating Expenses
From there, cap rate measures the property's return independent of financing:
Cap Rate = NOI ÷ Purchase Price × 100
Cash-on-cash return tells you what your actual invested dollars earn after the loan payment:
Cash-on-Cash = Annual Pre-Tax Cash Flow ÷ Total Cash Invested × 100
Here's what that actually means. Cap rate treats the property as if you paid all cash, so it's perfect for comparing two buildings on equal footing. Cash-on-cash factors in your mortgage and down payment, showing the real yield on the money you put in. A property can have a modest 5% cap rate but a strong 10% cash-on-cash return once leverage is applied. The calculator runs all three at once so you see both the property's quality and your personal return.
A green cash flow number is the headline, but the percentages tell the deeper story. In 2026, stabilized US single-family rentals typically post cap rates of 4.5–6.5%, with 6–7% considered strong. Cash-on-cash benchmarks run higher because of leverage — most investors target 8–12%, and anything above 6–7% is respectable in an appreciation market. If your calculator spits out a negative monthly cash flow, the property loses money every month and only works if you're betting heavily on appreciation. A thin 2–3% cash-on-cash return isn't automatically a dealbreaker in a fast-growing metro, but it leaves no cushion for a furnace replacement or two months of vacancy. Read the three numbers together: a high cap rate with negative cash flow usually signals an overpriced loan, while solid cash flow on a low cap rate often means you simply put a lot of cash down.
Small input changes swing these returns more than people expect. Watch these:
Even one empty month a year knocks roughly 8% off your gross rent. Budgeting zero vacancy is the fastest way to fool yourself.
Self-managing saves 8–10% of rent, but factor it in anyway — your time has value and you may eventually hand it off.
A bigger down payment lowers your loan and lifts cash flow, but it also dilutes cash-on-cash return because more capital is tied up.
Older properties demand bigger reserves. A common rule sets aside 1% of property value annually for repairs.
These vary wildly by state; Texas taxes can dwarf those in a low-rate state on the same priced home.
Modest annual rent increases compound, turning a break-even deal into a cash producer over several years.
You buy a $280,000 house in a growth metro, putting 25% down ($70,000) and financing $210,000 at 7.5% over 30 years — a payment near $1,468. Market rent is $2,100 a month, or $25,200 a year. Operating expenses (taxes, insurance, 8% management, maintenance, and a 7% vacancy reserve) run about $7,560, leaving NOI of $17,640. That's a cap rate of 6.3% ($17,640 ÷ $280,000). After the $17,616 annual mortgage, cash flow is roughly $24 a month — razor thin. With closing costs your cash invested is near $78,000, so cash-on-cash sits at about 0.4%. This deal only makes sense if you expect strong rent growth or appreciation.
A $220,000 duplex rents for $1,300 per unit, $2,600 total, or $31,200 a year. You put 25% down ($55,000) and finance $165,000 at 7.5%, a payment around $1,154. Expenses total about $9,360, giving NOI of $21,840 and a cap rate of 9.9%. After $13,848 in annual mortgage payments, you net roughly $666 a month, about $7,992 a year. On $60,000 all-in cash invested, that's a 13.3% cash-on-cash return. The duplex cash-flows far better because cheaper Midwest pricing pairs with higher relative rents.
Numbers on a screen only help if your inputs are honest. Keep these habits:
Underwrite conservatively. Use the low end of rent estimates and the high end of expenses. A deal that survives pessimistic numbers is a deal worth making.
Never skip vacancy and CapEx. These two phantom costs sink more new landlords than anything else. Build them in from day one.
Compare cap rate to local norms. A 5% cap is great in San Francisco and weak in Memphis. Context beats any universal benchmark.
Separate property quality from financing. Cap rate judges the building; cash-on-cash judges your loan. Improve one without confusing the other.
Re-run the deal at a higher rate. If it only works at today's exact interest rate, it's fragile.
Account for depreciation's tax benefit. It won't show in cash flow, but it can meaningfully boost your after-tax return.
A rental property calculator estimates a property's profitability by computing cap rate, monthly cash flow, and cash-on-cash return from the price, rent, loan, and expenses. It helps investors decide whether a deal is worth pursuing before making an offer. You enter the listing's numbers and it does the analysis instantly.
Cap rate equals net operating income divided by the purchase price, times 100. If a $280,000 property produces $17,640 in NOI, the cap rate is 6.3%. It measures return as if you bought the property in all cash, ignoring the mortgage.
A good cap rate for US single-family rentals in 2026 is generally 6–7%, with 4.5–6.5% being typical for stabilized homes. Growth metros often sit at 5–7%, while cash-flow markets in the Midwest and South can reach 7–9%. Lower isn't always bad if you expect strong appreciation.
Cash-on-cash return is your annual pre-tax cash flow divided by the total cash you invested. Most investors target 8–12% in 2026, though 6–7% is acceptable in appreciation markets. It reflects the actual yield on the money you put down.
Cap rate measures the property's return ignoring financing, while cash-on-cash measures the return on your invested cash after the mortgage. Cap rate compares deals on equal footing; cash-on-cash shows your personal yield. A property can have a low cap rate but a high cash-on-cash return thanks to leverage.
Include property taxes, insurance, property management, maintenance, repairs, a vacancy allowance, and any HOA fees. Operating expenses exclude the mortgage, which is handled separately in cash-flow math. Forgetting vacancy and maintenance reserves is the most common beginner mistake.
Depreciation doesn't reduce your cash flow, but it lowers your taxable income and can significantly improve your after-tax return. Residential rentals are depreciated over 27.5 years in the US. It's worth modeling separately once a deal clears your cash-flow test.
Brief disclaimer: This calculator provides estimates for educational and planning purposes only. Actual returns depend on local market conditions, financing terms, tenant behavior, and expense variability. Results should be treated as planning guidance rather than financial or investment advice.