.roi-calculator-container {
font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
max-width: 800px;
margin: 0 auto;
border: 1px solid #e0e0e0;
border-radius: 8px;
background: #fff;
box-shadow: 0 4px 6px rgba(0,0,0,0.05);
}
.roi-calc-header {
background: #2c3e50;
color: #fff;
padding: 20px;
border-radius: 8px 8px 0 0;
text-align: center;
}
.roi-calc-header h2 {
margin: 0;
font-size: 24px;
}
.roi-calc-body {
padding: 20px;
display: flex;
flex-wrap: wrap;
gap: 20px;
}
.roi-input-group {
flex: 1 1 300px;
}
.roi-input-field {
margin-bottom: 15px;
}
.roi-input-field label {
display: block;
font-weight: 600;
margin-bottom: 5px;
color: #333;
font-size: 14px;
}
.roi-input-field input {
width: 100%;
padding: 10px;
border: 1px solid #ccc;
border-radius: 4px;
box-sizing: border-box;
font-size: 16px;
}
.roi-input-field .input-suffix {
position: relative;
}
.roi-input-field .input-suffix span {
position: absolute;
right: 10px;
top: 10px;
color: #777;
}
.roi-btn {
width: 100%;
padding: 15px;
background: #27ae60;
color: white;
border: none;
border-radius: 4px;
font-size: 18px;
font-weight: bold;
cursor: pointer;
transition: background 0.3s;
}
.roi-btn:hover {
background: #219150;
}
.roi-results {
flex: 1 1 300px;
background: #f8f9fa;
padding: 20px;
border-radius: 8px;
border: 1px solid #e9ecef;
display: none;
}
.result-item {
margin-bottom: 15px;
padding-bottom: 10px;
border-bottom: 1px solid #e0e0e0;
display: flex;
justify-content: space-between;
align-items: center;
}
.result-item:last-child {
border-bottom: none;
}
.result-label {
font-size: 14px;
color: #555;
}
.result-value {
font-size: 18px;
font-weight: bold;
color: #2c3e50;
}
.highlight-result {
color: #27ae60;
font-size: 22px;
}
.roi-content-article {
max-width: 800px;
margin: 40px auto;
font-family: inherit;
line-height: 1.6;
color: #333;
}
.roi-content-article h2 {
color: #2c3e50;
border-bottom: 2px solid #eee;
padding-bottom: 10px;
margin-top: 30px;
}
.roi-content-article h3 {
color: #34495e;
margin-top: 25px;
}
.roi-content-article p {
margin-bottom: 15px;
}
.roi-content-article ul {
margin-bottom: 15px;
padding-left: 20px;
}
.roi-content-article li {
margin-bottom: 8px;
}
@media (max-width: 600px) {
.roi-calc-body {
flex-direction: column;
}
}
Investment Analysis
Monthly Mortgage (P&I):
$0.00
Total Monthly Costs:
$0.00
Monthly Cash Flow:
$0.00
Net Operating Income (NOI):
$0.00
Cap Rate:
0.00%
Cash on Cash Return:
0.00%
*Total costs include mortgage principal, interest, and operating expenses.
function calculateRentalROI() {
// Get Inputs
var purchasePrice = parseFloat(document.getElementById('purchasePrice').value);
var downPayment = parseFloat(document.getElementById('downPayment').value);
var closingCosts = parseFloat(document.getElementById('closingCosts').value);
var interestRate = parseFloat(document.getElementById('interestRate').value);
var loanTerm = parseFloat(document.getElementById('loanTerm').value);
var monthlyRent = parseFloat(document.getElementById('monthlyRent').value);
var monthlyExpenses = parseFloat(document.getElementById('monthlyExpenses').value);
// Validation
if (isNaN(purchasePrice) || isNaN(downPayment) || isNaN(interestRate) || isNaN(loanTerm) || isNaN(monthlyRent) || isNaN(monthlyExpenses)) {
alert("Please fill in all fields with valid numbers to calculate ROI.");
return;
}
if (isNaN(closingCosts)) {
closingCosts = 0;
}
// Mortgage Calculation
var loanAmount = purchasePrice – downPayment;
var monthlyInterestRate = (interestRate / 100) / 12;
var numberOfPayments = loanTerm * 12;
var monthlyMortgage = 0;
if (loanAmount > 0 && interestRate > 0) {
monthlyMortgage = loanAmount * (monthlyInterestRate * Math.pow(1 + monthlyInterestRate, numberOfPayments)) / (Math.pow(1 + monthlyInterestRate, numberOfPayments) – 1);
} else if (loanAmount > 0 && interestRate === 0) {
monthlyMortgage = loanAmount / numberOfPayments;
}
// Financial Metrics Calculation
var totalMonthlyCosts = monthlyMortgage + monthlyExpenses;
var monthlyCashFlow = monthlyRent – totalMonthlyCosts;
var annualCashFlow = monthlyCashFlow * 12;
var totalCashInvested = downPayment + closingCosts;
// NOI (Net Operating Income) = (Income – Operating Expenses excluding Mortgage) * 12
var annualNOI = (monthlyRent – monthlyExpenses) * 12;
// Cap Rate = (NOI / Purchase Price) * 100
var capRate = (annualNOI / purchasePrice) * 100;
// Cash on Cash Return = (Annual Cash Flow / Total Cash Invested) * 100
var cashOnCash = 0;
if (totalCashInvested > 0) {
cashOnCash = (annualCashFlow / totalCashInvested) * 100;
}
// Display Results
document.getElementById('resMortgage').innerText = "$" + monthlyMortgage.toLocaleString('en-US', {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById('resTotalCosts').innerText = "$" + totalMonthlyCosts.toLocaleString('en-US', {minimumFractionDigits: 2, maximumFractionDigits: 2});
// Color coding for cash flow
var cashFlowElem = document.getElementById('resCashFlow');
cashFlowElem.innerText = "$" + monthlyCashFlow.toLocaleString('en-US', {minimumFractionDigits: 2, maximumFractionDigits: 2});
cashFlowElem.style.color = monthlyCashFlow >= 0 ? "#27ae60" : "#c0392b";
document.getElementById('resNOI').innerText = "$" + annualNOI.toLocaleString('en-US', {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById('resCapRate').innerText = capRate.toFixed(2) + "%";
var cocElem = document.getElementById('resCoC');
cocElem.innerText = cashOnCash.toFixed(2) + "%";
cocElem.style.color = cashOnCash >= 0 ? "#27ae60" : "#c0392b";
// Show result box
document.getElementById('roiResults').style.display = "block";
}
Why Use a Rental Property ROI Calculator?
Investing in real estate is one of the most reliable ways to build wealth, but not every property is a good deal. A Rental Property ROI (Return on Investment) Calculator is an essential tool for investors to analyze the profitability of a potential purchase before signing any contracts.
This calculator helps you determine key financial metrics like Cash Flow, Cap Rate, and Cash-on-Cash Return. By inputting the purchase price, financing details, rental income, and operating expenses, you can immediately see if a property meets your investment criteria.
Understanding the Key Metrics
1. Cash Flow
Cash flow is the net amount of cash moving into or out of your investment each month. It is calculated by subtracting your total monthly expenses (mortgage, taxes, insurance, maintenance) from your monthly rental income. Positive cash flow ensures the property pays for itself and generates income.
2. Cash-on-Cash Return
Cash-on-Cash (CoC) Return measures the annual return on the actual cash you invested (down payment + closing costs). Unlike general ROI, which might look at the total asset value, CoC tells you how hard your specific dollars are working.
Example: If you invest $50,000 cash to buy a property and it generates $5,000 in net positive cash flow per year, your Cash-on-Cash return is 10%.
3. Cap Rate (Capitalization Rate)
Cap Rate indicates the rate of return on a real estate investment property based on the income that the property is expected to generate. It is calculated by dividing the Net Operating Income (NOI) by the property asset value. Cap rate is useful for comparing properties without factoring in mortgage financing, allowing for an "apples-to-apples" comparison of the property's raw earning potential.
How to Estimate Expenses
One of the biggest mistakes new investors make is underestimating expenses. When using the calculator, ensure you include:
- Property Taxes: usually 1-2% of the property value annually.
- Insurance: Obtain quotes for landlord insurance policies.
- Maintenance & Repairs: Budget 5-10% of monthly rent for future repairs.
- Vacancy Rate: Account for months where the property sits empty (often 5-8% of rent).
- Property Management: If you hire a manager, expect to pay 8-10% of the monthly rent.
Interpreting Your Results
There is no "perfect" number, but many investors aim for a Cash-on-Cash return of 8-12% or higher. A positive cash flow is critical for long-term sustainability. If the calculator shows negative cash flow, you would need to subsidize the property from your own pocket every month, which increases risk significantly.