.re-calculator-wrapper {
max-width: 800px;
margin: 20px auto;
font-family: 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
border: 1px solid #e0e0e0;
border-radius: 8px;
box-shadow: 0 4px 12px rgba(0,0,0,0.05);
background: #ffffff;
overflow: hidden;
}
.re-calc-header {
background: #2c3e50;
color: white;
padding: 20px;
text-align: center;
}
.re-calc-header h2 {
margin: 0;
font-size: 24px;
}
.re-calc-body {
padding: 25px;
display: flex;
flex-wrap: wrap;
gap: 30px;
}
.re-input-section {
flex: 1;
min-width: 300px;
}
.re-results-section {
flex: 1;
min-width: 300px;
background: #f8f9fa;
padding: 20px;
border-radius: 8px;
border: 1px solid #dee2e6;
}
.re-input-group {
margin-bottom: 15px;
}
.re-input-group label {
display: block;
margin-bottom: 5px;
font-weight: 600;
color: #333;
font-size: 14px;
}
.re-input-group input {
width: 100%;
padding: 10px;
border: 1px solid #ccc;
border-radius: 4px;
box-sizing: border-box;
font-size: 16px;
}
.re-btn {
width: 100%;
background: #27ae60;
color: white;
border: none;
padding: 15px;
font-size: 18px;
font-weight: bold;
border-radius: 4px;
cursor: pointer;
transition: background 0.3s;
margin-top: 10px;
}
.re-btn:hover {
background: #219150;
}
.re-result-row {
display: flex;
justify-content: space-between;
margin-bottom: 15px;
padding-bottom: 10px;
border-bottom: 1px solid #e9ecef;
}
.re-result-row:last-child {
border-bottom: none;
}
.re-result-label {
color: #555;
font-size: 15px;
}
.re-result-value {
font-weight: 700;
color: #2c3e50;
font-size: 16px;
}
.re-highlight {
color: #27ae60;
font-size: 20px;
}
.re-neg {
color: #c0392b;
}
.re-content-article {
max-width: 800px;
margin: 40px auto;
padding: 0 20px;
line-height: 1.6;
color: #333;
}
.re-content-article h2 {
color: #2c3e50;
margin-top: 30px;
}
.re-content-article h3 {
color: #27ae60;
}
.re-content-article ul {
margin-bottom: 20px;
}
.re-content-article li {
margin-bottom: 10px;
}
@media (max-width: 600px) {
.re-calc-body {
flex-direction: column;
}
}
Investment Analysis
Monthly Mortgage Payment:
$0.00
Total Monthly Expenses:
$0.00
Net Operating Income (NOI):
$0.00 / yr
Cap Rate:
0.00%
Cash on Cash Return:
0.00%
Est. Monthly Cash Flow:
$0.00
function calculateROI() {
// 1. Get Values
var price = parseFloat(document.getElementById('propPrice').value);
var downPayment = parseFloat(document.getElementById('downPay').value);
var rate = parseFloat(document.getElementById('intRate').value);
var term = parseFloat(document.getElementById('loanTerm').value);
var rent = parseFloat(document.getElementById('monthlyRent').value);
var expenses = parseFloat(document.getElementById('monthlyExp').value);
// Validation
if (isNaN(price) || isNaN(downPayment) || isNaN(rate) || isNaN(term) || isNaN(rent) || isNaN(expenses)) {
alert("Please enter valid numbers in all fields.");
return;
}
// 2. Calculate Mortgage
var loanAmount = price – downPayment;
var monthlyRate = rate / 100 / 12;
var numberOfPayments = term * 12;
var monthlyMortgage = 0;
if (rate === 0) {
monthlyMortgage = loanAmount / numberOfPayments;
} else {
monthlyMortgage = loanAmount * (monthlyRate * Math.pow(1 + monthlyRate, numberOfPayments)) / (Math.pow(1 + monthlyRate, numberOfPayments) – 1);
}
// 3. Calculate Metrics
var totalMonthlyExpenses = monthlyMortgage + expenses;
var monthlyCashFlow = rent – totalMonthlyExpenses;
var annualCashFlow = monthlyCashFlow * 12;
// NOI = (Gross Income – Operating Expenses) (Excluding Mortgage)
// Annual Operating Expenses = expenses * 12
var annualOperatingExpenses = expenses * 12;
var annualGrossIncome = rent * 12;
var noi = annualGrossIncome – annualOperatingExpenses;
// Cap Rate = (NOI / Property Price) * 100
var capRate = (noi / price) * 100;
// Cash on Cash Return = (Annual Pre-Tax Cash Flow / Total Cash Invested) * 100
// Assuming Cash Invested is just Down Payment for this simplified calculator
// Guard against divide by zero if 0 down payment
var cashOnCash = 0;
if (downPayment > 0) {
cashOnCash = (annualCashFlow / downPayment) * 100;
} else {
cashOnCash = 0; // Or infinite, but 0 is safer for display
}
// 4. Update UI
var formatter = new Intl.NumberFormat('en-US', {
style: 'currency',
currency: 'USD',
});
document.getElementById('resMortgage').innerText = formatter.format(monthlyMortgage);
document.getElementById('resTotalExp').innerText = formatter.format(totalMonthlyExpenses);
document.getElementById('resNOI').innerText = formatter.format(noi) + " / yr";
document.getElementById('resCashFlow').innerText = formatter.format(monthlyCashFlow);
document.getElementById('resCapRate').innerText = capRate.toFixed(2) + "%";
document.getElementById('resCoC').innerText = cashOnCash.toFixed(2) + "%";
// Styling for negative cash flow
var cfElement = document.getElementById('resCashFlow');
if (monthlyCashFlow < 0) {
cfElement.style.color = "#c0392b";
} else {
cfElement.style.color = "#27ae60";
}
}
Understanding Your Rental Property Investment Metrics
Investing in real estate requires more than just buying a property and finding a tenant. To ensure a profitable portfolio, investors must analyze key performance indicators (KPIs). This Rental Property Investment Calculator helps you evaluate the profitability of a potential purchase using three critical metrics: Cash Flow, Cap Rate, and Cash on Cash Return.
1. Net Operating Income (NOI)
NOI is a fundamental calculation used to analyze the profitability of income-generating real estate investments. It equals all revenue from the property, minus all reasonably necessary operating expenses. Note that NOI does not include mortgage payments (debt service).
Formula: Gross Income – Operating Expenses = NOI
2. Capitalization Rate (Cap Rate)
The Cap Rate indicates the rate of return that is expected to be generated on a real estate investment property. It helps you compare the return of a property regardless of how you pay for it (cash vs. loan).
- High Cap Rate: Typically implies higher risk but higher potential return. often found in developing neighborhoods.
- Low Cap Rate: Implies lower risk and lower return, often found in stabilized, high-demand areas.
Formula: (NOI / Purchase Price) × 100
3. Cash on Cash Return
While Cap Rate looks at the property's raw potential, Cash on Cash Return measures the return on the actual cash you invested (your down payment and closing costs). This is often the most important metric for investors using leverage (mortgages).
If your Cash on Cash return is lower than inflation or safe bond yields, the investment may not be worth the risk and effort of being a landlord.
How to Maximize Your ROI
To improve the numbers shown in the calculator above, investors typically look to:
- Increase Rent: Through renovations or better marketing.
- Decrease Expenses: By appealing property tax assessments or managing the property yourself.
- Refinance: Securing a lower interest rate to reduce debt service and increase monthly cash flow.