.rental-calculator-container {
font-family: 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
max-width: 800px;
margin: 0 auto;
background: #ffffff;
border: 1px solid #e0e0e0;
border-radius: 8px;
padding: 20px;
box-shadow: 0 4px 12px rgba(0,0,0,0.05);
}
.rental-calc-header {
text-align: center;
margin-bottom: 30px;
}
.rental-calc-header h2 {
margin: 0;
color: #2c3e50;
font-size: 28px;
}
.rental-calc-header p {
color: #7f8c8d;
font-size: 16px;
}
.calc-grid {
display: grid;
grid-template-columns: 1fr 1fr;
gap: 20px;
}
@media (max-width: 768px) {
.calc-grid {
grid-template-columns: 1fr;
}
}
.input-group {
margin-bottom: 15px;
}
.input-group label {
display: block;
margin-bottom: 5px;
font-weight: 600;
color: #34495e;
font-size: 14px;
}
.input-group input {
width: 100%;
padding: 10px;
border: 1px solid #bdc3c7;
border-radius: 4px;
font-size: 16px;
box-sizing: border-box;
transition: border 0.3s;
}
.input-group input:focus {
border-color: #27ae60;
outline: none;
}
.section-title {
grid-column: 1 / -1;
font-size: 18px;
color: #27ae60;
border-bottom: 2px solid #ecf0f1;
padding-bottom: 10px;
margin-top: 20px;
margin-bottom: 15px;
font-weight: bold;
}
.btn-container {
grid-column: 1 / -1;
display: flex;
gap: 10px;
margin-top: 20px;
}
.calc-btn {
background-color: #27ae60;
color: white;
border: none;
padding: 12px 24px;
border-radius: 4px;
font-size: 16px;
cursor: pointer;
flex: 1;
font-weight: bold;
transition: background 0.3s;
}
.calc-btn:hover {
background-color: #219150;
}
.reset-btn {
background-color: #95a5a6;
color: white;
border: none;
padding: 12px 24px;
border-radius: 4px;
font-size: 16px;
cursor: pointer;
width: 100px;
font-weight: bold;
}
.reset-btn:hover {
background-color: #7f8c8d;
}
.results-section {
grid-column: 1 / -1;
background-color: #f9fbfd;
border: 1px solid #dcdcdc;
border-radius: 6px;
padding: 20px;
margin-top: 30px;
display: none;
}
.result-row {
display: flex;
justify-content: space-between;
align-items: center;
padding: 10px 0;
border-bottom: 1px solid #eee;
}
.result-row:last-child {
border-bottom: none;
}
.result-label {
color: #555;
font-weight: 500;
}
.result-value {
font-weight: bold;
font-size: 18px;
color: #2c3e50;
}
.highlight-positive {
color: #27ae60;
}
.highlight-negative {
color: #c0392b;
}
.metric-box {
background: #fff;
padding: 15px;
border-radius: 4px;
text-align: center;
border: 1px solid #eee;
margin-top: 15px;
}
.metric-title {
font-size: 14px;
color: #7f8c8d;
text-transform: uppercase;
letter-spacing: 1px;
}
.metric-value {
font-size: 24px;
font-weight: 800;
color: #2c3e50;
margin-top: 5px;
}
.metrics-grid {
display: grid;
grid-template-columns: 1fr 1fr 1fr;
gap: 10px;
margin-bottom: 20px;
}
.article-content {
margin-top: 50px;
line-height: 1.6;
color: #333;
}
.article-content h3 {
color: #2c3e50;
margin-top: 30px;
}
.article-content ul {
padding-left: 20px;
}
.article-content li {
margin-bottom: 10px;
}
function validateInput(input) {
// Simple validation to prevent negative numbers
if (input.value 0 && interestRate > 0 && loanTerm > 0) {
var monthlyRate = (interestRate / 100) / 12;
var numberOfPayments = loanTerm * 12;
// M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1 ]
monthlyMortgage = loanAmount * (monthlyRate * Math.pow(1 + monthlyRate, numberOfPayments)) / (Math.pow(1 + monthlyRate, numberOfPayments) – 1);
} else if (loanAmount > 0 && interestRate === 0) {
monthlyMortgage = loanAmount / (loanTerm * 12);
}
// 3. Operating Expenses
var monthlyTax = annualTax / 12;
var monthlyInsurance = annualInsurance / 12;
var monthlyMaintenance = monthlyRent * (maintenancePercent / 100);
var monthlyOperatingExpenses = monthlyTax + monthlyInsurance + monthlyHOA + monthlyMaintenance;
// 4. Cash Flow
var totalMonthlyExpenses = monthlyOperatingExpenses + monthlyMortgage;
var monthlyCashFlow = monthlyRent – totalMonthlyExpenses;
var annualCashFlow = monthlyCashFlow * 12;
// 5. NOI (Net Operating Income)
var annualOperatingExpenses = monthlyOperatingExpenses * 12;
var annualNOI = (monthlyRent * 12) – annualOperatingExpenses;
// 6. Metrics
var capRate = 0;
if (price > 0) {
capRate = (annualNOI / price) * 100;
}
var cashOnCashROI = 0;
if (totalCashInvested > 0) {
cashOnCashROI = (annualCashFlow / totalCashInvested) * 100;
}
// Display Results
document.getElementById('results').style.display = 'block';
// Helper to format currency
var fmt = new Intl.NumberFormat('en-US', { style: 'currency', currency: 'USD' });
document.getElementById('monthlyCashFlow').innerHTML = fmt.format(monthlyCashFlow);
document.getElementById('monthlyCashFlow').className = monthlyCashFlow >= 0 ? "metric-value highlight-positive" : "metric-value highlight-negative";
document.getElementById('cashOnCash').innerHTML = cashOnCashROI.toFixed(2) + '%';
document.getElementById('cashOnCash').className = cashOnCashROI >= 0 ? "metric-value highlight-positive" : "metric-value highlight-negative";
document.getElementById('capRate').innerHTML = capRate.toFixed(2) + '%';
document.getElementById('resIncome').innerHTML = fmt.format(monthlyRent);
document.getElementById('resMortgage').innerHTML = fmt.format(monthlyMortgage);
document.getElementById('resExpenses').innerHTML = fmt.format(monthlyOperatingExpenses);
document.getElementById('resNOI').innerHTML = fmt.format(annualNOI);
document.getElementById('resTotalCash').innerHTML = fmt.format(totalCashInvested);
// Scroll to results
document.getElementById('results').scrollIntoView({ behavior: 'smooth' });
}
function resetCalculator() {
document.getElementById('purchasePrice').value = ";
document.getElementById('downPayment').value = '20';
document.getElementById('closingCosts').value = '5000';
document.getElementById('interestRate').value = '6.5';
document.getElementById('loanTerm').value = '30';
document.getElementById('monthlyRent').value = ";
document.getElementById('propertyTax').value = '3000';
document.getElementById('homeInsurance').value = '1200';
document.getElementById('hoaFees').value = '0';
document.getElementById('maintenance').value = '10';
document.getElementById('results').style.display = 'none';
}
Rental Property Calculator
Analyze cash flow, cap rate, and ROI for real estate investments.
Purchase Information
Income & Expenses
Cash Flow
–
/ Month
Cash on Cash ROI
–
Annual
Cap Rate
–
Annual
Monthly Rental Income
$0.00
Monthly Mortgage (P&I)
$0.00
Monthly Operating Expenses
$0.00
Net Operating Income (Annual)
$0.00
Total Cash Invested (Upfront)
$0.00
How to Calculate Rental Property ROI
Investing in rental real estate is one of the most reliable ways to build wealth, but simply buying a property doesn't guarantee a profit. To succeed, you must analyze the numbers effectively using three key metrics: Cash Flow, Cap Rate, and Cash on Cash Return.
1. Monthly Cash Flow
Cash flow is the net amount of money left in your pocket after all expenses are paid. It is calculated as:
Cash Flow = Total Monthly Income – (Operating Expenses + Mortgage Payment)
Positive cash flow ensures the property pays for itself and provides passive income. A common "safe" number for investors is $100-$200 per door per month, though this varies by market.
2. Capitalization Rate (Cap Rate)
The Cap Rate measures the natural rate of return of the property independent of how you financed it (i.e., if you bought it with cash). It helps you compare the profitability of different properties.
Cap Rate = (Net Operating Income / Purchase Price) × 100
- 4-6%: Common in high-appreciation, low-risk areas.
- 6-8%: A solid balance of risk and return.
- 8%+: Often found in riskier areas or undervalued markets.
3. Cash on Cash Return (ROI)
This is arguably the most important metric for investors using leverage (mortgages). It calculates the return on the actual cash you invested, not the total property price.
CoC ROI = (Annual Cash Flow / Total Cash Invested) × 100
"Total Cash Invested" includes your down payment, closing costs, and immediate repair costs. A CoC return of 8-12% is often considered a good target, beating the average stock market return.
Common Expenses to Watch
When using this calculator, ensure you don't underestimate expenses. Common oversights include:
- Vacancy: Properties aren't rented 365 days a year. Allocating 5-8% of rent for vacancy is prudent.
- Maintenance: Roofs leak and toilets break. Save 5-10% of monthly rent for future repairs (CapEx).
- Property Management: If you don't self-manage, expect to pay 8-10% of the monthly rent to a management company.