function calculateCapRate() {
var propValue = parseFloat(document.getElementById("propertyValue").value);
var rentalIncome = parseFloat(document.getElementById("annualRentalIncome").value);
var otherIncome = parseFloat(document.getElementById("otherIncome").value);
var vacancyRate = parseFloat(document.getElementById("vacancyRate").value);
var opExpenses = parseFloat(document.getElementById("operatingExpenses").value);
// Default otherIncome to 0 if empty
if (isNaN(otherIncome)) { otherIncome = 0; }
// Default vacancy to 0 if empty
if (isNaN(vacancyRate)) { vacancyRate = 0; }
// Validation
if (isNaN(propValue) || isNaN(rentalIncome) || isNaN(opExpenses)) {
alert("Please enter valid numbers for Price, Income, and Expenses.");
return;
}
if (propValue <= 0) {
alert("Property Value must be greater than zero.");
return;
}
// Calculations
var grossPotentialIncome = rentalIncome + otherIncome;
var vacancyLoss = grossPotentialIncome * (vacancyRate / 100);
var effectiveGrossIncome = grossPotentialIncome – vacancyLoss;
var netOperatingIncome = effectiveGrossIncome – opExpenses;
var capRate = (netOperatingIncome / propValue) * 100;
// Display Results
document.getElementById("resGrossIncome").innerText = "$" + grossPotentialIncome.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById("resVacancy").innerText = "-$" + vacancyLoss.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById("resEffectiveIncome").innerText = "$" + effectiveGrossIncome.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById("resNOI").innerText = "$" + netOperatingIncome.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
var capRateElement = document.getElementById("resCapRate");
capRateElement.innerText = capRate.toFixed(2) + "%";
// Color coding for negative NOI
if (netOperatingIncome < 0) {
document.getElementById("resNOI").style.color = "#e74c3c";
} else {
document.getElementById("resNOI").style.color = "#2c3e50";
}
document.getElementById("resultBox").style.display = "block";
}
Understanding the Capitalization Rate (Cap Rate)
In the world of real estate investing, the Capitalization Rate (or "Cap Rate") is one of the most fundamental metrics used to evaluate the profitability and return potential of an investment property. Unlike the Cash-on-Cash return, the Cap Rate assesses the property's yield independent of debt financing, allowing investors to compare properties "apples-to-apples" regardless of how they are purchased.
How is Cap Rate Calculated?
The Cap Rate formula determines the natural rate of return generated by the real estate asset. It is calculated by dividing the Net Operating Income (NOI) by the current market value (or purchase price) of the property.
Calculate Gross Potential Income: Sum the annual rent and any additional income streams (laundry, parking, etc.).
Subtract Vacancy Losses: Deduct the estimated revenue lost due to unit turnover or vacancy (typically 3-8% depending on the market).
Subtract Operating Expenses: Deduct all costs required to run the property, such as property taxes, insurance, maintenance, property management fees, and utilities. Note: Do not include mortgage payments (principal and interest) in this calculation.
Determine NOI: The remaining amount is your Net Operating Income.
Divide by Value: Divide the NOI by the purchase price to get the percentage return.
What is a "Good" Cap Rate?
There is no single percentage that defines a "good" Cap Rate, as it varies heavily based on location, asset class, and economic conditions. Generally, a higher Cap Rate implies a higher return, but it often comes with higher risk.
4% to 5%: Often found in Class A properties in hot markets (like NYC or San Francisco). These are low-risk, stabilized assets with high appreciation potential but lower immediate cash flow.
6% to 8%: A typical target for many residential and multifamily investors in stable, growing secondary markets. This usually offers a balance of cash flow and safety.
10% and above: Often associated with riskier assets, older buildings, or properties in declining neighborhoods. While the paper return looks high, the risk of vacancies and major repairs is also higher.
Cap Rate vs. Cash-on-Cash Return
It is crucial not to confuse Cap Rate with Cash-on-Cash return. Cap Rate assumes you bought the property entirely with cash. If you use a mortgage (leverage), your actual return on the cash you invested (down payment) will be different. Cap Rate is a measure of the property's performance, while Cash-on-Cash return is a measure of your investment's performance.
When to Use This Calculator
Use the calculator above when you are screening potential properties. It helps you quickly filter out overpriced deals. If a seller is asking $1,000,000 for a property that only generates $30,000 in NOI (a 3% Cap Rate), and the market average is 6%, you know the property is likely overpriced or requires significant value-add work to justify the investment.