#rental-cash-flow-calculator-wrapper {
font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
max-width: 800px;
margin: 0 auto;
padding: 20px;
color: #333;
line-height: 1.6;
}
.rcf-calc-card {
background: #f9f9f9;
border: 1px solid #e0e0e0;
border-radius: 8px;
padding: 30px;
box-shadow: 0 4px 6px rgba(0,0,0,0.05);
margin-bottom: 40px;
}
.rcf-header {
text-align: center;
margin-bottom: 25px;
color: #2c3e50;
}
.rcf-grid {
display: grid;
grid-template-columns: 1fr 1fr;
gap: 20px;
}
@media (max-width: 600px) {
.rcf-grid {
grid-template-columns: 1fr;
}
}
.rcf-input-group {
margin-bottom: 15px;
}
.rcf-input-group label {
display: block;
margin-bottom: 5px;
font-weight: 600;
font-size: 0.9rem;
color: #555;
}
.rcf-input-group input, .rcf-input-group select {
width: 100%;
padding: 10px;
border: 1px solid #ccc;
border-radius: 4px;
font-size: 1rem;
box-sizing: border-box;
}
.rcf-input-group input:focus {
border-color: #3498db;
outline: none;
box-shadow: 0 0 5px rgba(52,152,219,0.3);
}
.rcf-section-title {
grid-column: 1 / -1;
font-size: 1.1rem;
font-weight: bold;
margin-top: 10px;
margin-bottom: 10px;
color: #2980b9;
border-bottom: 2px solid #eee;
padding-bottom: 5px;
}
.rcf-btn {
grid-column: 1 / -1;
background-color: #27ae60;
color: white;
border: none;
padding: 15px;
font-size: 1.1rem;
font-weight: bold;
border-radius: 5px;
cursor: pointer;
transition: background 0.3s;
margin-top: 10px;
width: 100%;
}
.rcf-btn:hover {
background-color: #219150;
}
.rcf-results {
grid-column: 1 / -1;
background: #fff;
border: 1px solid #ddd;
border-radius: 6px;
padding: 20px;
margin-top: 20px;
display: none;
}
.rcf-result-row {
display: flex;
justify-content: space-between;
padding: 10px 0;
border-bottom: 1px solid #eee;
}
.rcf-result-row:last-child {
border-bottom: none;
}
.rcf-result-label {
font-weight: 500;
color: #666;
}
.rcf-result-value {
font-weight: 700;
color: #2c3e50;
}
.rcf-highlight {
background-color: #e8f8f5;
padding: 15px;
border-radius: 5px;
margin-top: 10px;
}
.rcf-highlight .rcf-result-value {
color: #27ae60;
font-size: 1.4rem;
}
.rcf-article h2 {
color: #2c3e50;
margin-top: 30px;
}
.rcf-article p {
margin-bottom: 15px;
}
.rcf-article ul {
margin-bottom: 15px;
padding-left: 20px;
}
.rcf-article li {
margin-bottom: 8px;
}
function calculateRentalCashFlow() {
// Get Inputs
var price = parseFloat(document.getElementById('rcf-price').value);
var downPercent = parseFloat(document.getElementById('rcf-down-percent').value);
var closingCosts = parseFloat(document.getElementById('rcf-closing-costs').value);
var interestRate = parseFloat(document.getElementById('rcf-interest').value);
var termYears = parseFloat(document.getElementById('rcf-term').value);
var monthlyRent = parseFloat(document.getElementById('rcf-rent').value);
var annualTax = parseFloat(document.getElementById('rcf-tax').value);
var annualInsurance = parseFloat(document.getElementById('rcf-insurance').value);
var monthlyHOA = parseFloat(document.getElementById('rcf-hoa').value);
var monthlyMaint = parseFloat(document.getElementById('rcf-maintenance').value);
var vacancyRate = parseFloat(document.getElementById('rcf-vacancy').value);
// Validation
if (isNaN(price) || isNaN(monthlyRent) || isNaN(interestRate) || isNaN(downPercent)) {
alert("Please enter valid numbers for Price, Rent, Interest Rate, and Down Payment.");
return;
}
// Handle optional fields as 0 if empty
if (isNaN(closingCosts)) closingCosts = 0;
if (isNaN(annualTax)) annualTax = 0;
if (isNaN(annualInsurance)) annualInsurance = 0;
if (isNaN(monthlyHOA)) monthlyHOA = 0;
if (isNaN(monthlyMaint)) monthlyMaint = 0;
if (isNaN(vacancyRate)) vacancyRate = 0;
// 1. Calculate Loan Details
var downPaymentAmount = price * (downPercent / 100);
var loanAmount = price – downPaymentAmount;
// Monthly Interest Rate
var monthlyRate = (interestRate / 100) / 12;
var numberOfPayments = termYears * 12;
// Mortgage Calculation (P&I)
var monthlyMortgage = 0;
if (monthlyRate > 0) {
monthlyMortgage = loanAmount * (monthlyRate * Math.pow(1 + monthlyRate, numberOfPayments)) / (Math.pow(1 + monthlyRate, numberOfPayments) – 1);
} else {
monthlyMortgage = loanAmount / numberOfPayments;
}
// 2. Calculate Effective Income
var vacancyCost = monthlyRent * (vacancyRate / 100);
var effectiveIncome = monthlyRent – vacancyCost;
// 3. Calculate Expenses
var monthlyTax = annualTax / 12;
var monthlyInsurance = annualInsurance / 12;
var totalOperatingExpenses = monthlyTax + monthlyInsurance + monthlyHOA + monthlyMaint;
// Total Monthly Outflow (Operating Expenses + Mortgage)
var totalMonthlyExpenses = totalOperatingExpenses + monthlyMortgage;
// 4. Calculate Key Metrics
var noi = effectiveIncome – totalOperatingExpenses; // Net Operating Income (Monthly)
var cashFlow = effectiveIncome – totalMonthlyExpenses;
var annualCashFlow = cashFlow * 12;
var totalInitialInvestment = downPaymentAmount + closingCosts;
// Cash on Cash Return
var cocReturn = 0;
if (totalInitialInvestment > 0) {
cocReturn = (annualCashFlow / totalInitialInvestment) * 100;
}
// Format Currency
var formatter = new Intl.NumberFormat('en-US', {
style: 'currency',
currency: 'USD',
});
// Display Results
document.getElementById('res-loan-amount').innerHTML = formatter.format(loanAmount);
document.getElementById('res-mortgage').innerHTML = formatter.format(monthlyMortgage);
document.getElementById('res-expenses').innerHTML = formatter.format(totalMonthlyExpenses); // Includes P&I for the display summary
document.getElementById('res-noi').innerHTML = formatter.format(noi);
var cashFlowEl = document.getElementById('res-cashflow');
cashFlowEl.innerHTML = formatter.format(cashFlow);
// Styling logic for positive/negative cash flow
if (cashFlow >= 0) {
cashFlowEl.style.color = "#27ae60";
} else {
cashFlowEl.style.color = "#c0392b";
}
document.getElementById('res-coc').innerHTML = cocReturn.toFixed(2) + "%";
// Show result area
document.getElementById('rcf-result-area').style.display = 'block';
}
Rental Property Cash Flow Calculator
Purchase Details
Loan Details
30 Years
20 Years
15 Years
10 Years
Income & Expenses
Financial Analysis
Loan Amount:
$0.00
Monthly Principal & Interest:
$0.00
Total Monthly Expenses:
$0.00
Net Operating Income (NOI) / Mo:
$0.00
Est. Monthly Cash Flow:
$0.00
Cash-on-Cash Return:
0.00%
Understanding Rental Property Cash Flow
Investing in real estate is one of the most reliable ways to build wealth, but simply buying a property doesn't guarantee a profit. The most critical metric for any buy-and-hold real estate investor is Cash Flow. This Rental Property Cash Flow Calculator is designed to help you quickly analyze a potential deal to see if it makes financial sense.
What is Positive Cash Flow?
Positive cash flow occurs when the gross income from your rental property exceeds all the expenses associated with owning and operating it. Expenses include your mortgage payment, taxes, insurance, homeowner association (HOA) fees, repairs, and vacancy allowances. If you have $200 left over at the end of the month after paying all bills, you have positive cash flow.
Key Terms in This Calculator
- NOI (Net Operating Income): This is your total income minus operating expenses (taxes, insurance, maintenance), but excluding the mortgage payment. It is a pure measure of the property's profitability before debt.
- Cash-on-Cash Return: This metric compares your annual pre-tax cash flow to the total cash you actually invested (down payment + closing costs). It tells you how hard your money is working for you compared to other investments like stocks or bonds.
- Vacancy Rate: It is unrealistic to assume your property will be rented 365 days a year forever. A vacancy rate (typically 5-8%) accounts for turnover periods between tenants where you receive no income but still pay expenses.
The 1% Rule of Thumb
When quickly screening properties, many investors use the "1% Rule." This rule suggests that the monthly rent should be at least 1% of the purchase price. For example, a $200,000 home should rent for at least $2,000 per month. While this rule is a good starting point, using a detailed calculator like the one above is essential to account for interest rates, high taxes, or HOA fees that the 1% rule ignores.
How to Improve Cash Flow
If the calculator shows negative or low cash flow, consider these adjustments: negotiating a lower purchase price, increasing the down payment to lower the mortgage, shopping for cheaper insurance, or value-adding renovations that justify a higher rent.