.rp-calculator-wrapper {
max-width: 800px;
margin: 0 auto;
font-family: 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
color: #333;
background: #fff;
border: 1px solid #e0e0e0;
border-radius: 8px;
box-shadow: 0 4px 12px rgba(0,0,0,0.05);
padding: 30px;
}
.rp-calculator-header {
text-align: center;
margin-bottom: 30px;
}
.rp-calculator-header h2 {
color: #2c3e50;
margin: 0 0 10px 0;
}
.rp-calculator-grid {
display: grid;
grid-template-columns: 1fr 1fr;
gap: 20px;
}
@media (max-width: 768px) {
.rp-calculator-grid {
grid-template-columns: 1fr;
}
}
.rp-input-group {
margin-bottom: 15px;
}
.rp-input-group label {
display: block;
margin-bottom: 5px;
font-weight: 600;
font-size: 0.9em;
color: #555;
}
.rp-input-group input {
width: 100%;
padding: 10px;
border: 1px solid #ccc;
border-radius: 4px;
font-size: 16px;
box-sizing: border-box;
}
.rp-input-group input:focus {
border-color: #3498db;
outline: none;
box-shadow: 0 0 5px rgba(52,152,219,0.3);
}
.rp-calc-btn {
grid-column: 1 / -1;
background-color: #27ae60;
color: white;
border: none;
padding: 15px;
font-size: 18px;
font-weight: bold;
border-radius: 4px;
cursor: pointer;
transition: background-color 0.3s;
margin-top: 10px;
width: 100%;
}
.rp-calc-btn:hover {
background-color: #219150;
}
.rp-results-section {
grid-column: 1 / -1;
background-color: #f8f9fa;
border-left: 5px solid #3498db;
padding: 20px;
margin-top: 20px;
border-radius: 4px;
display: none; /* Hidden by default */
}
.rp-result-row {
display: flex;
justify-content: space-between;
margin-bottom: 10px;
padding-bottom: 10px;
border-bottom: 1px solid #e9ecef;
}
.rp-result-row:last-child {
border-bottom: none;
margin-bottom: 0;
padding-bottom: 0;
}
.rp-result-label {
font-weight: 600;
color: #7f8c8d;
}
.rp-result-value {
font-weight: 700;
font-size: 1.1em;
color: #2c3e50;
}
.rp-result-value.positive {
color: #27ae60;
}
.rp-result-value.negative {
color: #c0392b;
}
.rp-content-article {
max-width: 800px;
margin: 40px auto;
line-height: 1.6;
color: #444;
}
.rp-content-article h2 {
color: #2c3e50;
margin-top: 30px;
border-bottom: 2px solid #eee;
padding-bottom: 10px;
}
.rp-content-article h3 {
color: #34495e;
margin-top: 25px;
}
.rp-content-article ul {
margin-bottom: 20px;
padding-left: 20px;
}
.rp-content-article li {
margin-bottom: 10px;
}
.rp-error-msg {
color: #c0392b;
text-align: center;
margin-top: 10px;
font-weight: bold;
display: none;
}
function calculateRentalROI() {
// 1. Get Inputs
var price = parseFloat(document.getElementById('rp_price').value);
var down = parseFloat(document.getElementById('rp_down').value);
var rate = parseFloat(document.getElementById('rp_rate').value);
var term = parseFloat(document.getElementById('rp_term').value);
var rent = parseFloat(document.getElementById('rp_rent').value);
var expenses = parseFloat(document.getElementById('rp_expenses').value);
var errorDiv = document.getElementById('rp_error');
var resultDiv = document.getElementById('rp_results');
// 2. Validation
if (isNaN(price) || isNaN(down) || isNaN(rate) || isNaN(term) || isNaN(rent) || isNaN(expenses)) {
errorDiv.style.display = 'block';
resultDiv.style.display = 'none';
return;
}
if (price <= 0 || term 0 && monthlyRate > 0) {
mortgagePayment = (loanAmount * monthlyRate * Math.pow(1 + monthlyRate, numPayments)) / (Math.pow(1 + monthlyRate, numPayments) – 1);
} else if (loanAmount > 0 && monthlyRate === 0) {
mortgagePayment = loanAmount / numPayments;
}
// Total Monthly Outflow
var totalMonthlyExpenses = mortgagePayment + expenses;
// Net Operating Income (NOI) – Annualized (Income – Operating Expenses, excluding mortgage)
var annualNOI = (rent – expenses) * 12;
// Monthly Cash Flow
var monthlyCashFlow = rent – totalMonthlyExpenses;
var annualCashFlow = monthlyCashFlow * 12;
// Cash on Cash ROI = (Annual Cash Flow / Total Cash Invested) * 100
// Assuming Total Cash Invested is just the Down Payment for this simple calculator
var cashOnCash = 0;
if (down > 0) {
cashOnCash = (annualCashFlow / down) * 100;
}
// Cap Rate = (NOI / Purchase Price) * 100
var capRate = 0;
if (price > 0) {
capRate = (annualNOI / price) * 100;
}
// 4. Output Formatting
document.getElementById('res_mortgage').innerText = '$' + mortgagePayment.toFixed(2);
document.getElementById('res_total_exp').innerText = '$' + totalMonthlyExpenses.toFixed(2);
var cfElement = document.getElementById('res_cashflow');
cfElement.innerText = '$' + monthlyCashFlow.toFixed(2);
cfElement.className = 'rp-result-value ' + (monthlyCashFlow >= 0 ? 'positive' : 'negative');
var cocElement = document.getElementById('res_coc');
cocElement.innerText = cashOnCash.toFixed(2) + '%';
cocElement.className = 'rp-result-value ' + (cashOnCash >= 0 ? 'positive' : 'negative');
document.getElementById('res_cap').innerText = capRate.toFixed(2) + '%';
// Show results
resultDiv.style.display = 'block';
}
Is Your Rental Property a Good Investment?
Real estate investing is one of the most powerful ways to build wealth, but it relies heavily on the numbers. Buying a property because it "looks nice" is a recipe for financial disaster. Successful investors rely on key metrics like Cash Flow, Cash-on-Cash Return, and Cap Rate to determine if a deal makes sense.
This Rental Property Cash Flow Calculator is designed to give you an immediate snapshot of your potential investment's profitability. By inputting your purchase costs, financing terms, and operating expenses, you can see exactly how much money goes into your pocket every month.
Understanding the Key Metrics
1. Monthly Cash Flow
Cash flow is the lifeblood of any rental investment. It is the money left over after all expenses—including the mortgage, taxes, insurance, and maintenance—have been paid.
Formula: Rental Income – (Mortgage + Expenses) = Cash Flow
Positive cash flow means the asset pays for itself and provides income. Negative cash flow implies you are losing money every month to hold the property.
2. Cash-on-Cash ROI
This metric calculates the return on the actual cash you invested (usually your down payment and closing costs), rather than the total price of the home. It allows you to compare real estate returns against other investments like stocks or bonds.
For example, if you invest $50,000 as a down payment and the property generates $5,000 in net cash flow per year, your Cash-on-Cash return is 10%.
3. Cap Rate (Capitalization Rate)
The Cap Rate measures the property's natural rate of return assuming you bought it with all cash (no loan). It is calculated by dividing the Net Operating Income (NOI) by the Purchase Price. This is crucial for comparing the profitability of different properties regardless of how they are financed.
How to Estimate Expenses
One of the biggest mistakes new investors make is underestimating expenses. When using the calculator above, ensure your "Monthly Expenses" field includes:
- Property Taxes: Usually 1-2% of the property value annually.
- Insurance: Landlord policies differ from homeowner policies.
- Vacancy: Assume the property will sit empty for 5-8% of the year.
- Repairs & CapEx: Set aside 5-10% of rent for future roof replacements, HVAC repairs, etc.
- Property Management: If you hire a manager, deduct 8-10% of the rent.
Example Calculation
Let's say you buy a property for $200,000 with a $40,000 down payment (20%). You get a 30-year loan at 6.5% interest.
- Rental Income: $2,000/month
- Mortgage Payment: ~$1,011/month
- Operating Expenses (Taxes, Ins, Repairs): ~$600/month
- Total Outflow: $1,611/month
- Net Cash Flow: $389/month ($4,668/year)
- Cash-on-Cash ROI: 11.6%
This example demonstrates a healthy investment with positive cash flow and a double-digit return on cash invested.