#rental-calculator-wrapper {
font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
max-width: 800px;
margin: 0 auto;
background: #fff;
padding: 20px;
border-radius: 8px;
box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}
.calc-grid {
display: grid;
grid-template-columns: 1fr 1fr;
gap: 20px;
}
@media (max-width: 600px) {
.calc-grid {
grid-template-columns: 1fr;
}
}
.input-group {
margin-bottom: 15px;
}
.input-group label {
display: block;
margin-bottom: 5px;
font-weight: 600;
color: #333;
font-size: 0.9em;
}
.input-group input {
width: 100%;
padding: 10px;
border: 1px solid #ddd;
border-radius: 4px;
font-size: 16px;
box-sizing: border-box;
}
.input-group input:focus {
border-color: #2c3e50;
outline: none;
}
.calc-section-title {
grid-column: 1 / -1;
font-size: 1.1em;
color: #2c3e50;
border-bottom: 2px solid #eee;
padding-bottom: 10px;
margin-top: 10px;
margin-bottom: 15px;
font-weight: bold;
}
button.calc-btn {
grid-column: 1 / -1;
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;
}
button.calc-btn:hover {
background: #219150;
}
#results-area {
display: none; /* Hidden by default */
margin-top: 30px;
background: #f9f9f9;
padding: 20px;
border-radius: 8px;
border: 1px solid #eee;
}
.result-cards {
display: grid;
grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
gap: 15px;
margin-bottom: 20px;
}
.result-card {
background: white;
padding: 15px;
border-radius: 6px;
text-align: center;
box-shadow: 0 2px 5px rgba(0,0,0,0.05);
}
.result-card.highlight {
background: #e8f8f5;
border: 1px solid #27ae60;
}
.result-label {
display: block;
font-size: 0.85em;
color: #666;
margin-bottom: 5px;
text-transform: uppercase;
letter-spacing: 0.5px;
}
.result-value {
font-size: 1.4em;
font-weight: 800;
color: #2c3e50;
}
.positive { color: #27ae60; }
.negative { color: #c0392b; }
.breakdown-list {
list-style: none;
padding: 0;
margin: 0;
}
.breakdown-list li {
display: flex;
justify-content: space-between;
padding: 8px 0;
border-bottom: 1px solid #eee;
font-size: 0.95em;
}
.breakdown-list li:last-child {
border-bottom: none;
}
.calc-article {
margin-top: 40px;
line-height: 1.6;
color: #444;
}
.calc-article h2 {
color: #2c3e50;
margin-top: 30px;
}
.calc-article h3 {
color: #34495e;
margin-top: 20px;
}
.calc-article ul {
padding-left: 20px;
}
function calculateRental() {
// 1. Get Input Values
var price = parseFloat(document.getElementById('purchasePrice').value) || 0;
var downPct = parseFloat(document.getElementById('downPaymentPct').value) || 0;
var rate = parseFloat(document.getElementById('interestRate').value) || 0;
var term = parseFloat(document.getElementById('loanTerm').value) || 0;
var monthlyRent = parseFloat(document.getElementById('monthlyRent').value) || 0;
var annualTax = parseFloat(document.getElementById('annualTax').value) || 0;
var annualIns = parseFloat(document.getElementById('annualInsurance').value) || 0;
var monthlyHOA = parseFloat(document.getElementById('monthlyHOA').value) || 0;
var vacancyPct = parseFloat(document.getElementById('vacancyRate').value) || 0;
var maintPct = parseFloat(document.getElementById('maintenanceRate').value) || 0;
// 2. Calculate Loan Details
var downPaymentAmt = price * (downPct / 100);
var loanAmount = price – downPaymentAmt;
// Mortgage Calculation (P&I)
var monthlyRate = (rate / 100) / 12;
var numPayments = term * 12;
var monthlyMortgage = 0;
if (rate === 0) {
monthlyMortgage = loanAmount / numPayments;
} else {
monthlyMortgage = (loanAmount * monthlyRate) / (1 – Math.pow(1 + monthlyRate, -numPayments));
}
// 3. Calculate Expenses
var monthlyTax = annualTax / 12;
var monthlyIns = annualIns / 12;
var vacancyCost = monthlyRent * (vacancyPct / 100);
var maintCost = monthlyRent * (maintPct / 100);
var operatingExpenses = monthlyTax + monthlyIns + monthlyHOA + vacancyCost + maintCost;
var totalMonthlyExpenses = operatingExpenses + monthlyMortgage;
// 4. Calculate Returns
var effectiveIncome = monthlyRent – vacancyCost;
var cashFlow = effectiveIncome – (monthlyMortgage + monthlyTax + monthlyIns + monthlyHOA + maintCost);
// Net Operating Income (Annual) = (Income – Operating Expenses) * 12. Note: NOI excludes Mortgage.
var annualNOI = (effectiveIncome – (monthlyTax + monthlyIns + monthlyHOA + maintCost)) * 12;
// Cash Invested (Down Payment + Estimated Closing Costs of 3%)
var closingCosts = price * 0.03;
var totalCashInvested = downPaymentAmt + closingCosts;
var annualCashFlow = cashFlow * 12;
var cashOnCash = 0;
if (totalCashInvested > 0) {
cashOnCash = (annualCashFlow / totalCashInvested) * 100;
}
var capRate = 0;
if (price > 0) {
capRate = (annualNOI / price) * 100;
}
// 5. Update UI
// Helper for currency formatting
var fmt = new Intl.NumberFormat('en-US', { style: 'currency', currency: 'USD' });
// Main Results
var cfElement = document.getElementById('resCashFlow');
cfElement.innerHTML = fmt.format(cashFlow);
cfElement.className = "result-value " + (cashFlow >= 0 ? "positive" : "negative");
var cocElement = document.getElementById('resCoc');
cocElement.innerHTML = cashOnCash.toFixed(2) + "%";
cocElement.className = "result-value " + (cashOnCash >= 0 ? "positive" : "negative");
document.getElementById('resCapRate').innerHTML = capRate.toFixed(2) + "%";
// Breakdowns
document.getElementById('outGrossRent').innerHTML = fmt.format(monthlyRent);
document.getElementById('outVacancy').innerHTML = "-" + fmt.format(vacancyCost);
document.getElementById('outEffectiveIncome').innerHTML = fmt.format(effectiveIncome);
document.getElementById('outMortgage').innerHTML = fmt.format(monthlyMortgage);
document.getElementById('outTaxIns').innerHTML = fmt.format(monthlyTax + monthlyIns);
document.getElementById('outMaintHOA').innerHTML = fmt.format(maintCost + monthlyHOA);
document.getElementById('outTotalExp').innerHTML = fmt.format(totalMonthlyExpenses);
// Show Results Area
document.getElementById('results-area').style.display = "block";
}
Property Info & Loan Details
Income & Expenses
Monthly Cash Flow
$0.00
Cash on Cash Return
0.00%
Cap Rate
0.00%
Monthly Income Breakdown
- Gross Rent $0
- Vacancy Loss -$0
- Effective Income $0
Monthly Expense Breakdown
- Mortgage (P&I) $0
- Tax & Insurance $0
- Maintenance & HOA $0
- Total Expenses $0
How to Analyze a Rental Property Deal
Investing in real estate is a numbers game. While the aesthetics of a house matter, the math determines whether an asset is a liability or a wealth-building machine. This Rental Property Cash Flow Calculator is designed to help investors look past the "sticker price" and understand the true profitability of a potential investment.
Understanding the Key Metrics
When analyzing a rental property, there are three primary metrics you should focus on to ensure the investment aligns with your financial goals:
- Monthly Cash Flow: This is the net profit you pocket every month after all operating expenses and mortgage payments are made. Positive cash flow is essential for long-term sustainability. It is calculated as Effective Gross Income – Total Expenses.
- Cash on Cash Return (CoC): This measures the annual return on the actual cash you invested (down payment + closing costs), rather than the total purchase price. It allows you to compare real estate returns against other investment vehicles like stocks or bonds. A healthy CoC in many markets is often considered 8-12%.
- Cap Rate (Capitalization Rate): This metric indicates the rate of return on the property assuming it was bought entirely with cash. It is calculated by dividing the Net Operating Income (NOI) by the current market value. Cap Rate helps you compare the profitability of similar properties in the same market, regardless of financing.
How to Use This Calculator
- Property Details: Enter the purchase price and your loan terms. A typical conventional investment loan requires 20-25% down.
- Income: Input the expected monthly rent. Be realistic—check local comps (comparables) on sites like Zillow or Rentometer.
- Expenses: Do not underestimate expenses!
- Vacancy: Even in hot markets, tenants leave. A 5% vacancy rate (about 18 days a year) is a standard conservative estimate.
- Maintenance & CapEx: Roofs leak and water heaters break. Allocating 10-15% of rent for repairs is crucial for accurate forecasting.
By accurately inputting these variables, you can mitigate risk and make data-driven decisions on your journey to financial freedom through real estate.