Rental Property Calculator
Is this rental worth buying? Enter the price, loan, rent and expenses to see monthly cash flow, cap rate, cash-on-cash return, net operating income and the rent you need to break even.
How to use the rental property calculator
Enter the price and how you will finance it, the rent you expect, and every operating cost. The calculator shows monthly cash flow after the mortgage, the property's cap rate and net operating income, your cash-on-cash return on the money you put in, and the rent at which the property breaks even. The mortgage rate starts at Freddie Mac's weekly 30-year average (7.32% as of October 22, 2026) plus 0.75 point, as an example: lenders usually price loans on investment properties higher than on a home you live in, so use the rate you are quoted.
A worked example
Hypothetical: a $250,000 house bought with 25% down and $7,500 of closing costs, a 8.125% 30-year loan, rent of $2,000 a month, 5% vacancy, $2,400 of property tax and $1,500 of insurance a year, 5% of rent each for maintenance and replacements, and 8% for a property manager.
| Monthly | Amount |
|---|---|
| Rent after vacancy | $1,900 |
| Operating expenses | -$677 |
| Mortgage payment | -$1,392 |
| Cash flow | -$169 |
Cap rate 5.9%, cash-on-cash return -2.9% on $70,000 invested, break-even rent $2,219 a month. Managing it yourself changes the cash flow to -$17 a month; buying with cash, to $1,223 a month on $257,500 invested (5.7%). At today's rates, financing is often what turns a rental's cash flow negative.
What the numbers mean
- Net operating income (NOI): rent and other income after vacancy, minus operating expenses, before the mortgage.
- Cap rate: NOI divided by the price. It lets you compare properties as if each were bought with cash.
- Cash flow: what is left each month after the mortgage too. Negative means you pay in.
- Cash-on-cash return: a year of cash flow divided by the cash you put in (down payment, closing costs and repairs).
- Break-even rent: the rent at which cash flow is exactly zero with your other inputs.
Before you buy a rental
Cash flow is only part of the picture: being a landlord takes time, repairs arrive unevenly, and a single long vacancy can wipe out a year's profit. Our guide to the pros and cons of owning rental properties covers the work and risks, and is real estate a good investment compares it with stocks and REITs. If you would rather own real estate without tenants, see REITs.
Frequently Asked Questions
What is a good cash-on-cash return?
There is no official benchmark. Compare it with what the same cash would earn elsewhere with less work and risk, such as a high-yield savings account or an index fund, and remember cash-on-cash ignores appreciation and the loan principal you pay down.
What is the difference between cap rate and cash-on-cash return?
Cap rate is net operating income divided by the price, as if you paid cash: it compares properties regardless of financing. Cash-on-cash return is the yearly cash flow after the mortgage divided by the cash you actually put in, so it changes with your down payment and loan rate.
What is the 1% rule in real estate?
A quick screen used by investors: monthly rent of at least 1% of the purchase price. It is a rough filter, not a calculation; taxes, insurance and rates vary so much by area that a property can pass the rule and still lose money, or fail it and still work.
What expenses should I include for a rental property?
Property tax, landlord insurance, HOA dues, utilities you pay, repairs and maintenance, a reserve for big replacements such as the roof, HVAC and appliances, property management if you hire it, and vacancy. Leaving any of them out makes cash flow look better than it will be.
Does the calculator include taxes and appreciation?
No. It shows cash flow only. Rental income is taxable, depreciation and expenses can offset it, and the property may rise or fall in value. Talk to a tax professional about your situation.
