Rental Property ROI Calculator: Cash Flow & Cap Rate

AllinPlus Editorial Team Technical Research & Engineering Board

Published Jul 13, 2026 • Updated Jul 13, 2026

Calculate monthly cash flow, Cap Rate, Cash-on-Cash return, and total ROI for your next rental property investment. Use this real estate investment calculator to quickly run the numbers and see if a deal makes sense.

Property & financing

Purchase price

Down payment

Closing costs

Interest rate

Loan term

yrs

Income

Monthly rent

Other monthly income

Vacancy rate % of time unoccupied

Operating expenses

Annual property tax

Annual insurance

Maintenance % of rent

Property mgmt % of rent

HOA / other monthly costs

Growth assumptions

Annual appreciation

Rent / expense growth

Monthly cash flow

—

After mortgage, vacancy & operating expenses.

Cap rate

—

Net operating income Ã· purchase price. Ignores financing.

Cash-on-cash return

—

Annual cash flow Ã· actual cash invested.

Cash invested

—

Annual NOI

—

DSCR

—

Monthly cash flow breakdown

Gross rental income—

Vacancy loss—

Operating expenses—

Mortgage payment (P&I)—

Net monthly cash flow—

Total return (equity + cash flow) Cash invested

Total return over your hold period

If you hold forâ€¦ 10 years

NOI and cap rate exclude financing costs. Cash-on-cash return and total return account for your actual cash invested (down payment + closing costs). Total return assumes rent and operating expenses grow at the same rate, and that the mortgage payment stays fixed. Excludes income taxes, depreciation benefits, and selling costs at exit.

How to Use

Step 1: Enter the purchase price, down payment, and loan terms.
Step 2: Input the expected monthly rent and vacancy rate.
Step 3: Add operating expenses such as taxes, insurance, maintenance, and property management.
Step 4: Review your monthly cash flow, Cap Rate, and total return over time.

Example Calculation

Scenario: Buying a single-family home to rent out.

Price: ,000
Down Payment: 20% (,000)
Rent: ,600/month

Result: Monthly Cash Flow: | Cap Rate: 5.76%

After paying the mortgage, taxes, insurance, and accounting for vacancy and maintenance, the property nets per month. This yields a healthy Cash-on-Cash return of 5.94%.

Frequently Asked Questions

What is a good Cap Rate for a rental property?

A good Cap Rate typically falls between 4% and 10%, depending on the risk and location of the property. Lower Cap Rates usually indicate lower risk and higher potential for appreciation.

How is Cash-on-Cash return different from Cap Rate?

Cap Rate measures the return on the property assuming it was bought with all cash. Cash-on-Cash return measures the return on the actual cash you invested, factoring in the leverage of a mortgage.