.rpc-header { text-align: center; margin-bottom: 30px; }
.rpc-header h2 { color: #2c3e50; font-size: 28px; margin-bottom: 10px; }
.rpc-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
@media (max-width: 600px) { .rpc-grid { grid-template-columns: 1fr; } }
.rpc-input-group { margin-bottom: 15px; }
.rpc-input-group label { display: block; margin-bottom: 5px; color: #34495e; font-weight: 600; font-size: 14px; }
.rpc-input-group input { width: 100%; padding: 10px; border: 1px solid #ddd; border-radius: 4px; font-size: 16px; box-sizing: border-box; }
.rpc-input-group input:focus { border-color: #3498db; outline: none; }
.rpc-btn { grid-column: 1 / -1; background: #27ae60; color: white; border: none; padding: 15px; font-size: 18px; font-weight: bold; border-radius: 5px; cursor: pointer; transition: background 0.3s; width: 100%; margin-top: 10px; }
.rpc-btn:hover { background: #219150; }
.rpc-results { grid-column: 1 / -1; background: #f8f9fa; padding: 20px; border-radius: 5px; border-left: 5px solid #27ae60; margin-top: 20px; display: none; }
.rpc-result-item { display: flex; justify-content: space-between; margin-bottom: 10px; border-bottom: 1px solid #eee; padding-bottom: 5px; }
.rpc-result-item:last-child { border-bottom: none; }
.rpc-result-label { color: #555; }
.rpc-result-value { font-weight: bold; color: #2c3e50; }
.rpc-main-metric { font-size: 24px; color: #27ae60; font-weight: 800; text-align: center; margin: 15px 0; }
.rpc-metric-label { text-align: center; font-size: 14px; color: #7f8c8d; text-transform: uppercase; letter-spacing: 1px; }
.rpc-article { margin-top: 40px; color: #444; line-height: 1.6; }
.rpc-article h3 { color: #2c3e50; margin-top: 25px; border-bottom: 2px solid #eee; padding-bottom: 10px; }
.rpc-article ul { margin-left: 20px; }
.rpc-article li { margin-bottom: 8px; }
function calculateRentalROI() {
// 1. Get Input Values
var price = parseFloat(document.getElementById('purchasePrice').value);
var down = parseFloat(document.getElementById('downPayment').value);
var rate = parseFloat(document.getElementById('interestRate').value);
var term = parseFloat(document.getElementById('loanTerm').value);
var rent = parseFloat(document.getElementById('monthlyRent').value);
var tax = parseFloat(document.getElementById('annualTax').value);
var insurance = parseFloat(document.getElementById('annualInsurance').value);
var otherCosts = parseFloat(document.getElementById('monthlyCosts').value);
// Validation
if (isNaN(price) || isNaN(down) || isNaN(rate) || isNaN(term) || isNaN(rent) || isNaN(tax) || isNaN(insurance) || isNaN(otherCosts)) {
alert("Please enter valid numbers in all fields.");
return;
}
// 2. Calculate Mortgage (P&I)
var loanAmount = price – down;
var monthlyRate = (rate / 100) / 12;
var numPayments = term * 12;
// Handle edge case of 0% interest
var mortgagePayment = 0;
if (rate === 0) {
mortgagePayment = loanAmount / numPayments;
} else {
mortgagePayment = loanAmount * (monthlyRate * Math.pow(1 + monthlyRate, numPayments)) / (Math.pow(1 + monthlyRate, numPayments) – 1);
}
// 3. Calculate Monthly Expenses
var monthlyTax = tax / 12;
var monthlyIns = insurance / 12;
var totalMonthlyExpenses = mortgagePayment + monthlyTax + monthlyIns + otherCosts;
// 4. Calculate Key Metrics
var monthlyCashFlow = rent – totalMonthlyExpenses;
var annualCashFlow = monthlyCashFlow * 12;
// NOI = Annual Income – Operating Expenses (Excluding Debt Service)
// Operating Expenses = Tax + Insurance + Maintenance/HOA (otherCosts)
var annualOperatingExpenses = tax + insurance + (otherCosts * 12);
var annualNOI = (rent * 12) – annualOperatingExpenses;
var capRate = (annualNOI / price) * 100;
var cashOnCash = (annualCashFlow / down) * 100;
// 5. Update HTML
document.getElementById('resultMortgage').innerHTML = "$" + mortgagePayment.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById('resultExpenses').innerHTML = "$" + totalMonthlyExpenses.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
var cashFlowElement = document.getElementById('resultCashFlow');
cashFlowElement.innerHTML = "$" + monthlyCashFlow.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
// Color coding for Cash Flow
if (monthlyCashFlow >= 0) {
cashFlowElement.style.color = "#27ae60";
} else {
cashFlowElement.style.color = "#c0392b";
}
document.getElementById('resultNOI').innerHTML = "$" + annualNOI.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById('resultCapRate').innerHTML = capRate.toFixed(2) + "%";
document.getElementById('resultCoC').innerHTML = cashOnCash.toFixed(2) + "%";
// Show results div
document.getElementById('rpcResults').style.display = "block";
}
Rental Property Cash Flow Calculator
Analyze your real estate investment deal to determine monthly cash flow, Cap Rate, and ROI.
Estimated Monthly Cash Flow
$0.00
Monthly Mortgage (P&I):
$0.00
Total Monthly Expenses:
$0.00
Net Operating Income (Annual):
$0.00
Cap Rate:
0.00%
Cash on Cash Return:
0.00%
How to Calculate Rental Property ROI
Investing in rental property is a powerful way to build wealth, but understanding the numbers is critical to avoiding bad deals. This Rental Property Cash Flow Calculator helps investors evaluate the profitability of a potential real estate purchase by breaking down income, expenses, and debt service.
Key Metrics Explained
When analyzing a deal, you shouldn't rely on just one number. Here is what the metrics above mean for your investment:
- Monthly Cash Flow: This is your profit after all bills are paid. It is calculated as Monthly Rent – (Mortgage + Taxes + Insurance + Maintenance). Positive cash flow ensures the property pays for itself.
- Cap Rate (Capitalization Rate): Measures the natural rate of return on the property independent of debt. It is calculated by dividing the Annual Net Operating Income (NOI) by the Purchase Price. A higher Cap Rate generally indicates a better return, though often with higher risk.
- Cash on Cash Return (CoC): This is arguably the most important metric for investors using leverage. It measures the annual cash return on the actual money you invested (Down Payment). A CoC return of 8-12% is often considered a strong target for buy-and-hold investors.
The 1% Rule
A common rule of thumb in real estate is the "1% Rule," which states that the monthly rent should be at least 1% of the purchase price. While this calculator provides a more detailed analysis, the 1% rule serves as a quick filter. For example, a $200,000 home should rent for at least $2,000/month to likely be cash-flow positive.
Estimating Expenses
Many new investors underestimate expenses. Beyond the mortgage, ensure you account for vacancy (typically 5-8%), repairs (5-10%), and Capital Expenditures (replacing roofs, HVAC, etc.). This calculator includes a field for "Monthly Maint/HOA/CapEx" to help you factor these costs into your bottom line.