function calculateInvestmentROI() {
var purchasePrice = parseFloat(document.getElementById('purchasePrice').value);
var closingCosts = parseFloat(document.getElementById('closingCosts').value);
var monthlyRent = parseFloat(document.getElementById('monthlyRent').value);
var monthlyExpenses = parseFloat(document.getElementById('monthlyExpenses').value);
if (isNaN(purchasePrice) || isNaN(closingCosts) || isNaN(monthlyRent) || isNaN(monthlyExpenses)) {
alert("Please enter valid numeric values for all fields.");
return;
}
var totalInvestment = purchasePrice + closingCosts;
var annualGrossIncome = monthlyRent * 12;
var annualExpenses = monthlyExpenses * 12;
var annualCashFlow = annualGrossIncome – annualExpenses;
var roi = (annualCashFlow / totalInvestment) * 100;
var capRate = (annualCashFlow / purchasePrice) * 100;
document.getElementById('resTotalInvest').innerText = "$" + totalInvestment.toLocaleString();
document.getElementById('resAnnualCash').innerText = "$" + annualCashFlow.toLocaleString();
document.getElementById('resCapRate').innerText = capRate.toFixed(2) + "%";
document.getElementById('resROI').innerText = roi.toFixed(2) + "%";
document.getElementById('roi-results-area').style.display = 'block';
}
Understanding Your Investment Property ROI
Investing in real estate is one of the most proven ways to build long-term wealth, but success depends on accurately calculating your potential returns before signing a contract. Our Investment Property ROI Calculator is designed to help real estate investors determine the profitability of a rental property by looking at the two most critical metrics: the Cap Rate and the Cash-on-Cash Return (ROI).
How to Calculate Rental Property ROI
ROI, or Return on Investment, measures how much money you make on an investment as a percentage of the cost of that investment. In real estate, we specifically look at the cash you've put into the deal versus the annual profit generated after all expenses are paid.
The Formula for ROI
To calculate your return, use the following steps:
Calculate Net Operating Income (NOI): (Monthly Rent × 12) – (Monthly Operating Expenses × 12).
Calculate ROI: (Annual Cash Flow / Total Investment) × 100.
Cap Rate vs. ROI: What's the Difference?
While often used interchangeably, these two metrics tell different stories:
Cap Rate (Capitalization Rate): This calculates the return based strictly on the purchase price, ignoring any financing or closing costs. It is used to compare the natural profitability of one property against another in the same market.
ROI (Cash-on-Cash Return): This is the more "real-world" metric for most investors. It accounts for every dollar you actually spent (including repairs and closing costs) to get the property running.
Realistic Example: Single-Family Rental
Imagine you are looking at a property with the following numbers:
Metric
Value
Purchase Price
$200,000
Closing/Repairs
$10,000
Monthly Rent
$1,800
Monthly Expenses
$500
Resulting ROI
7.43%
Factors That Impact Your ROI
When using an ROI calculator, remember that "Monthly Expenses" should include more than just a mortgage (if applicable). Experienced investors always factor in:
Property Taxes: These can fluctuate based on local assessments.
Insurance: Landlord policies are typically more expensive than standard homeowner policies.
Vacancy Rate: It is wise to set aside 5-10% of your rent for months when the property is empty.
Maintenance & CapEx: Roofs, HVAC systems, and plumbing eventually need replacement.
Property Management: If you aren't managing it yourself, expect to pay 8-12% of the gross rent to a manager.
By using this tool, you can filter out "bad" deals quickly and focus your time and capital on properties that provide the highest return for your portfolio.