:root {
–primary-color: #2c3e50;
–accent-color: #27ae60;
–bg-color: #f4f7f6;
–text-color: #333;
–border-radius: 8px;
}
body {
font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
line-height: 1.6;
color: var(–text-color);
max-width: 1200px;
margin: 0 auto;
padding: 20px;
background-color: #fff;
}
.calculator-wrapper {
background: #fff;
border: 1px solid #e0e0e0;
border-radius: var(–border-radius);
box-shadow: 0 4px 6px rgba(0,0,0,0.05);
display: flex;
flex-wrap: wrap;
margin-bottom: 40px;
overflow: hidden;
}
.calc-inputs {
flex: 1 1 400px;
padding: 30px;
background-color: #fafafa;
border-right: 1px solid #eee;
}
.calc-results {
flex: 1 1 300px;
padding: 30px;
background-color: var(–primary-color);
color: #fff;
display: flex;
flex-direction: column;
justify-content: center;
}
h2 {
margin-top: 0;
color: var(–primary-color);
}
.form-group {
margin-bottom: 15px;
}
.form-group label {
display: block;
margin-bottom: 5px;
font-weight: 600;
font-size: 0.9rem;
}
.form-group input {
width: 100%;
padding: 10px;
border: 1px solid #ccc;
border-radius: 4px;
font-size: 1rem;
box-sizing: border-box; /* Fix padding issue */
}
.form-row {
display: flex;
gap: 15px;
}
.form-row .form-group {
flex: 1;
}
button.calc-btn {
width: 100%;
padding: 12px;
background-color: var(–accent-color);
color: white;
border: none;
border-radius: 4px;
font-size: 1rem;
font-weight: bold;
cursor: pointer;
margin-top: 10px;
transition: background 0.2s;
}
button.calc-btn:hover {
background-color: #219150;
}
.result-item {
margin-bottom: 20px;
border-bottom: 1px solid rgba(255,255,255,0.1);
padding-bottom: 10px;
}
.result-item:last-child {
border-bottom: none;
}
.result-label {
font-size: 0.9rem;
opacity: 0.9;
margin-bottom: 5px;
}
.result-value {
font-size: 1.5rem;
font-weight: 700;
}
.result-value.positive {
color: #2ecc71;
}
.result-value.negative {
color: #e74c3c;
}
.content-section {
margin-top: 40px;
padding: 20px;
background: #fff;
}
.content-section h2 {
border-bottom: 2px solid var(–accent-color);
padding-bottom: 10px;
margin-bottom: 20px;
}
.content-section h3 {
color: var(–primary-color);
margin-top: 25px;
}
.content-section ul {
margin-bottom: 20px;
}
.content-section li {
margin-bottom: 10px;
}
@media (max-width: 768px) {
.calculator-wrapper {
flex-direction: column;
}
.calc-inputs {
border-right: none;
border-bottom: 1px solid #eee;
}
}
Rental Property Cash Flow Calculator
Real estate investing is one of the most powerful ways to build wealth, but simply buying a property doesn't guarantee a profit. The difference between a liability and an asset often comes down to one metric: Cash Flow. This Rental Property Cash Flow Calculator is designed to help investors analyze deals quickly and accurately, ensuring you make data-driven decisions.
Why Calculate Cash Flow?
Cash flow is the net income from a real estate investment after mortgage payments and operating expenses have been made. Positive cash flow ensures the property pays for itself and provides you with passive income. Negative cash flow means you are paying out of pocket to hold the property, which increases your risk.
Using this calculator helps you:
- Identify profitable deals: Separate good investments from bad ones instantly.
- Plan for expenses: Account for "hidden" costs like vacancy, maintenance, and CapEx.
- Compare financing options: See how different down payments and interest rates affect your bottom line.
Understanding Key Metrics
1. Monthly Cash Flow
This is your "take-home" money every month. It is calculated as:
Rental Income – (Mortgage + Taxes + Insurance + HOA + Maintenance + Vacancy Reserves).
2. Cash on Cash Return (CoC)
This metric measures the return on the actual cash you invested (Down Payment + Closing Costs). It is often considered the most important metric for new investors because it shows how hard your money is working for you.
Formula: (Annual Cash Flow / Total Cash Invested) x 100
3. Cap Rate (Capitalization Rate)
Cap Rate measures the property's natural rate of return assuming you bought it in cash (no mortgage). It helps compare the profitability of the property itself, excluding your financing method.
Formula: (Net Operating Income / Purchase Price) x 100
How to Use This Calculator
To get the most accurate results, ensure you are inputting realistic numbers:
- Purchase Price: The agreed-upon price of the property.
- Down Payment: Typically 20-25% for investment properties.
- Vacancy Rate: Always budget for vacancy. A standard safe estimate is 5-8% (about 2-3 weeks of vacancy per year).
- Maintenance: Even if the house is new, things break. Set aside 5-10% of rent for repairs.
Example Scenario
Imagine you buy a property for $200,000 with 20% down. The rent is $2,000/month. Your mortgage is roughly $1,000, and total other expenses (taxes, insurance, repairs) are $500. Your cash flow is $500/month. If you invested $45,000 total (down payment + closing), your Cash on Cash return is ($6,000 / $45,000) = 13.3%, which is a solid return compared to the stock market.
function calculateRental() {
// 1. Get Input Values
var price = parseFloat(document.getElementById('purchasePrice').value);
var downPercent = parseFloat(document.getElementById('downPayment').value);
var interestRate = parseFloat(document.getElementById('interestRate').value);
var termYears = parseFloat(document.getElementById('loanTerm').value);
var closingCosts = parseFloat(document.getElementById('closingCosts').value);
var monthlyRent = parseFloat(document.getElementById('rentalIncome').value);
var yearlyTax = parseFloat(document.getElementById('propertyTax').value);
var yearlyIns = parseFloat(document.getElementById('insurance').value);
var monthlyHOA = parseFloat(document.getElementById('hoa').value);
var monthlyMaint = parseFloat(document.getElementById('maintenance').value);
var vacancyPercent = parseFloat(document.getElementById('vacancyRate').value);
// Validation to prevent NaN errors
if (isNaN(price) || isNaN(monthlyRent)) {
alert("Please enter valid numbers for Price and Rent.");
return;
}
// 2. Calculate Mortgage (P&I)
var downAmount = price * (downPercent / 100);
var loanAmount = price – downAmount;
var monthlyRate = (interestRate / 100) / 12;
var numPayments = termYears * 12;
var monthlyMortgage = 0;
if (interestRate === 0) {
monthlyMortgage = loanAmount / numPayments;
} else {
monthlyMortgage = (loanAmount * monthlyRate * Math.pow(1 + monthlyRate, numPayments)) / (Math.pow(1 + monthlyRate, numPayments) – 1);
}
// 3. Calculate Operating Expenses
var monthlyTax = yearlyTax / 12;
var monthlyIns = yearlyIns / 12;
var monthlyVacancy = monthlyRent * (vacancyPercent / 100);
var totalMonthlyOpEx = monthlyTax + monthlyIns + monthlyHOA + monthlyMaint + monthlyVacancy;
var totalMonthlyExpenses = monthlyMortgage + totalMonthlyOpEx;
// 4. Calculate Cash Flow
var monthlyCashFlow = monthlyRent – totalMonthlyExpenses;
var yearlyCashFlow = monthlyCashFlow * 12;
// 5. Calculate Metrics
// NOI = Income – Operating Expenses (Excluding Mortgage)
var annualNOI = (monthlyRent – totalMonthlyOpEx) * 12;
// Cap Rate = (NOI / Price) * 100
var capRate = (price > 0) ? (annualNOI / price) * 100 : 0;
// Cash Invested = Down Payment + Closing Costs
var totalCashInvested = downAmount + closingCosts;
// CoC Return = (Yearly Cash Flow / Total Cash Invested) * 100
var cocReturn = (totalCashInvested > 0) ? (yearlyCashFlow / totalCashInvested) * 100 : 0;
// 6. Display Results
// Helper to format currency
var fmtMoney = new Intl.NumberFormat('en-US', { style: 'currency', currency: 'USD' });
document.getElementById('resCashFlow').innerText = fmtMoney.format(monthlyCashFlow);
document.getElementById('resMortgage').innerText = fmtMoney.format(monthlyMortgage);
document.getElementById('resTotalExp').innerText = fmtMoney.format(totalMonthlyExpenses);
document.getElementById('resCoc').innerText = cocReturn.toFixed(2) + "%";
document.getElementById('resCapRate').innerText = capRate.toFixed(2) + "%";
// Styling for positive/negative cash flow
var cashFlowEl = document.getElementById('resCashFlow');
if (monthlyCashFlow >= 0) {
cashFlowEl.classList.remove('negative');
cashFlowEl.classList.add('positive');
} else {
cashFlowEl.classList.remove('positive');
cashFlowEl.classList.add('negative');
}
}
// Run initial calculation on load
window.onload = function() {
calculateRental();
};