Rental Property Cash Flow Calculator
.rpc-calculator-container {
font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
max-width: 800px;
margin: 20px auto;
padding: 25px;
background: #f9f9f9;
border: 1px solid #e0e0e0;
border-radius: 8px;
box-shadow: 0 4px 6px rgba(0,0,0,0.05);
}
.rpc-calculator-container h2 {
text-align: center;
color: #2c3e50;
margin-bottom: 25px;
}
.rpc-form-grid {
display: grid;
grid-template-columns: 1fr 1fr;
gap: 20px;
}
.rpc-input-group {
margin-bottom: 15px;
}
.rpc-input-group label {
display: block;
font-weight: 600;
margin-bottom: 5px;
color: #444;
font-size: 14px;
}
.rpc-input-group input, .rpc-input-group select {
width: 100%;
padding: 10px;
border: 1px solid #ccc;
border-radius: 4px;
font-size: 16px;
box-sizing: border-box;
}
.rpc-input-group input:focus {
border-color: #2980b9;
outline: none;
}
.rpc-section-title {
grid-column: 1 / -1;
font-size: 18px;
font-weight: bold;
color: #2980b9;
margin-top: 10px;
border-bottom: 2px solid #ddd;
padding-bottom: 5px;
margin-bottom: 15px;
}
.rpc-btn-container {
grid-column: 1 / -1;
text-align: center;
margin-top: 20px;
}
button.rpc-calculate-btn {
background-color: #27ae60;
color: white;
border: none;
padding: 12px 30px;
font-size: 18px;
font-weight: bold;
border-radius: 5px;
cursor: pointer;
transition: background-color 0.2s;
}
button.rpc-calculate-btn:hover {
background-color: #219150;
}
#rpc-result {
grid-column: 1 / -1;
background: #fff;
border: 1px solid #ddd;
border-radius: 5px;
padding: 20px;
margin-top: 25px;
display: none;
}
.rpc-result-grid {
display: grid;
grid-template-columns: 1fr 1fr 1fr;
gap: 15px;
text-align: center;
}
.rpc-result-item {
padding: 10px;
background: #f1f8ff;
border-radius: 5px;
}
.rpc-result-label {
font-size: 13px;
color: #666;
margin-bottom: 5px;
}
.rpc-result-value {
font-size: 20px;
font-weight: bold;
color: #2c3e50;
}
.rpc-result-highlight {
grid-column: 1 / -1;
background-color: #e8f8f5;
border: 1px solid #27ae60;
padding: 15px;
margin-top: 15px;
}
.rpc-result-highlight .rpc-result-value {
color: #27ae60;
font-size: 28px;
}
.rpc-content-article {
max-width: 800px;
margin: 40px auto;
font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
line-height: 1.6;
color: #333;
}
.rpc-content-article h2 {
color: #2c3e50;
margin-top: 30px;
}
.rpc-content-article h3 {
color: #34495e;
font-size: 1.2em;
margin-top: 20px;
}
.rpc-content-article p {
margin-bottom: 15px;
}
.rpc-content-article ul {
margin-bottom: 20px;
padding-left: 20px;
}
@media (max-width: 600px) {
.rpc-form-grid, .rpc-result-grid {
grid-template-columns: 1fr;
}
}
Rental Property Cash Flow Calculator
function calculateCashFlow() {
// 1. Get input values
var price = parseFloat(document.getElementById("purchasePrice").value) || 0;
var rent = parseFloat(document.getElementById("monthlyRent").value) || 0;
var downPercent = parseFloat(document.getElementById("downPayment").value) || 0;
var rate = parseFloat(document.getElementById("interestRate").value) || 0;
var term = parseFloat(document.getElementById("loanTerm").value) || 0;
var taxAnnual = parseFloat(document.getElementById("propertyTax").value) || 0;
var insuranceAnnual = parseFloat(document.getElementById("insurance").value) || 0;
var maintPercent = parseFloat(document.getElementById("maintenance").value) || 0;
var vacancyPercent = parseFloat(document.getElementById("vacancy").value) || 0;
// 2. Calculations
var downPaymentAmount = price * (downPercent / 100);
var loanAmount = price – downPaymentAmount;
// Mortgage Calculation (M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1])
var monthlyRate = (rate / 100) / 12;
var numPayments = term * 12;
var monthlyMortgage = 0;
if (rate > 0) {
monthlyMortgage = loanAmount * (monthlyRate * Math.pow(1 + monthlyRate, numPayments)) / (Math.pow(1 + monthlyRate, numPayments) – 1);
} else {
monthlyMortgage = loanAmount / numPayments;
}
// Monthly Expenses
var monthlyTax = taxAnnual / 12;
var monthlyInsurance = insuranceAnnual / 12;
var monthlyVacancy = rent * (vacancyPercent / 100);
var monthlyMaintenance = rent * (maintPercent / 100);
// Operating Expenses (Expenses without Mortgage)
var monthlyOperatingExpenses = monthlyTax + monthlyInsurance + monthlyVacancy + monthlyMaintenance;
// Total Expenses (With Mortgage)
var totalMonthlyExpenses = monthlyOperatingExpenses + monthlyMortgage;
// NOI (Net Operating Income) = Income – Operating Expenses
var monthlyNOI = rent – monthlyOperatingExpenses;
var annualNOI = monthlyNOI * 12;
// Cash Flow
var monthlyCashFlow = rent – totalMonthlyExpenses;
var annualCashFlow = monthlyCashFlow * 12;
// Investment Returns
var totalCashInvested = downPaymentAmount;
// Note: In a more complex calc we would add closing costs, but we'll stick to down payment for simplicity here.
var cashOnCash = 0;
if (totalCashInvested > 0) {
cashOnCash = (annualCashFlow / totalCashInvested) * 100;
}
var capRate = 0;
if (price > 0) {
capRate = (annualNOI / price) * 100;
}
// 3. Update DOM
document.getElementById("resIncome").innerText = "$" + rent.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById("resExpenses").innerText = "$" + totalMonthlyExpenses.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById("resNOI").innerText = "$" + monthlyNOI.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById("resMortgage").innerText = "$" + monthlyMortgage.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById("resCoC").innerText = cashOnCash.toFixed(2) + "%";
document.getElementById("resCap").innerText = capRate.toFixed(2) + "%";
var cfElement = document.getElementById("resCashFlow");
cfElement.innerText = "$" + monthlyCashFlow.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
// Style adjustment for negative cash flow
if (monthlyCashFlow < 0) {
cfElement.style.color = "#c0392b";
} else {
cfElement.style.color = "#27ae60";
}
document.getElementById("rpc-result").style.display = "block";
}
Understanding Rental Property Cash Flow
Investing in rental real estate is a powerful way to build wealth, but the numbers must make sense. The Rental Property Cash Flow Calculator helps investors analyze a potential deal by breaking down income, operating expenses, and financing costs to determine the true profitability of an asset.
What is Cash Flow?
Cash flow is the net amount of money left over each month after all expenses are paid. It is calculated as:
- Gross Rental Income (Rent collected)
- Minus Operating Expenses (Taxes, Insurance, Repairs, Vacancy)
- Minus Debt Service (Mortgage Principal & Interest)
Positive cash flow means the property pays for itself and provides you with passive income. Negative cash flow means you are losing money every month to hold the property.
Key Metrics Defined
This calculator provides several critical metrics to evaluate your investment:
- NOI (Net Operating Income): The annual income generated by the property after deducting operating expenses but before deducting mortgage payments. This is crucial for calculating Cap Rate.
- Cash on Cash Return (CoC): This measures the annual return on the actual cash you invested (down payment + closing costs). For example, if you invest $50,000 and make $5,000 in annual cash flow, your CoC return is 10%. This is often considered the most important metric for investors using leverage.
- Cap Rate (Capitalization Rate): The rate of return on the property based on the income it generates, assuming you paid cash. It helps compare different properties regardless of financing.
How to Use This Calculator
To get an accurate result, ensure you account for "hidden" costs. Many new investors forget to budget for Vacancy (months where the property sits empty) and Maintenance (saving for future repairs like a new roof or water heater). A common rule of thumb is to set aside 5% to 10% of monthly rent for each of these categories.