.calculator-container {
max-width: 800px;
margin: 20px auto;
padding: 25px;
background: #f9f9f9;
border: 1px solid #e0e0e0;
border-radius: 8px;
font-family: Arial, sans-serif;
}
.calculator-title {
text-align: center;
color: #333;
margin-bottom: 20px;
}
.input-grid {
display: grid;
grid-template-columns: 1fr 1fr;
gap: 20px;
}
@media (max-width: 600px) {
.input-grid {
grid-template-columns: 1fr;
}
}
.form-group {
margin-bottom: 15px;
}
.form-group label {
display: block;
margin-bottom: 5px;
font-weight: bold;
color: #555;
}
.form-group input {
width: 100%;
padding: 10px;
border: 1px solid #ccc;
border-radius: 4px;
box-sizing: border-box;
}
.section-header {
grid-column: 1 / -1;
margin-top: 10px;
margin-bottom: 10px;
border-bottom: 2px solid #ddd;
padding-bottom: 5px;
color: #2c3e50;
}
.calc-btn {
display: block;
width: 100%;
padding: 15px;
background-color: #27ae60;
color: white;
border: none;
border-radius: 4px;
font-size: 18px;
cursor: pointer;
margin-top: 20px;
transition: background 0.3s;
}
.calc-btn:hover {
background-color: #219150;
}
.results-section {
margin-top: 30px;
padding: 20px;
background: #fff;
border: 1px solid #ddd;
border-radius: 4px;
display: none;
}
.result-row {
display: flex;
justify-content: space-between;
padding: 10px 0;
border-bottom: 1px solid #eee;
}
.result-row:last-child {
border-bottom: none;
}
.result-value {
font-weight: bold;
color: #2c3e50;
}
.positive-flow {
color: #27ae60;
}
.negative-flow {
color: #c0392b;
}
.article-content {
max-width: 800px;
margin: 40px auto;
font-family: Arial, sans-serif;
line-height: 1.6;
color: #444;
}
.article-content h2 {
color: #2c3e50;
margin-top: 30px;
}
.article-content p {
margin-bottom: 15px;
}
.article-content ul {
margin-bottom: 15px;
padding-left: 20px;
}
function calculateCashFlow() {
// Get Inputs
var price = parseFloat(document.getElementById('purchasePrice').value);
var downPercent = parseFloat(document.getElementById('downPayment').value);
var rate = parseFloat(document.getElementById('interestRate').value);
var years = parseFloat(document.getElementById('loanTerm').value);
var income = parseFloat(document.getElementById('rentIncome').value);
var tax = parseFloat(document.getElementById('propertyTax').value);
var ins = parseFloat(document.getElementById('insurance').value);
var maint = parseFloat(document.getElementById('maintenance').value);
var hoa = parseFloat(document.getElementById('hoaFees').value);
var vacancyRate = parseFloat(document.getElementById('vacancy').value);
// Validation
if (isNaN(price) || isNaN(downPercent) || isNaN(rate) || isNaN(years) || isNaN(income)) {
alert("Please enter valid numbers for all key fields.");
return;
}
// Set defaults for optional fields if empty
if (isNaN(tax)) tax = 0;
if (isNaN(ins)) ins = 0;
if (isNaN(maint)) maint = 0;
if (isNaN(hoa)) hoa = 0;
if (isNaN(vacancyRate)) vacancyRate = 0;
// Mortgage Calculation
var downPaymentAmount = price * (downPercent / 100);
var loanAmount = price – downPaymentAmount;
var monthlyRate = (rate / 100) / 12;
var numPayments = years * 12;
var mortgagePayment = 0;
if (rate > 0) {
mortgagePayment = loanAmount * (monthlyRate * Math.pow(1 + monthlyRate, numPayments)) / (Math.pow(1 + monthlyRate, numPayments) – 1);
} else {
mortgagePayment = loanAmount / numPayments;
}
// Vacancy Loss
var vacancyLoss = income * (vacancyRate / 100);
var effectiveIncome = income – vacancyLoss;
// Expenses
var totalOperatingExpenses = tax + ins + maint + hoa;
var totalExpensesWithMortgage = totalOperatingExpenses + mortgagePayment;
// Key Metrics
var monthlyCashFlow = effectiveIncome – totalExpensesWithMortgage;
var annualCashFlow = monthlyCashFlow * 12;
// NOI (Net Operating Income) = Income – Operating Expenses (excluding financing)
var monthlyNOI = effectiveIncome – totalOperatingExpenses;
var annualNOI = monthlyNOI * 12;
// ROI (Cash on Cash)
var initialInvestment = downPaymentAmount; // Simplified to just down payment
var roi = 0;
if (initialInvestment > 0) {
roi = (annualCashFlow / initialInvestment) * 100;
}
// Cap Rate
var capRate = 0;
if (price > 0) {
capRate = (annualNOI / price) * 100;
}
// Display Results
document.getElementById('results').style.display = 'block';
var flowElem = document.getElementById('resCashFlow');
flowElem.innerText = "$" + monthlyCashFlow.toFixed(2);
if (monthlyCashFlow >= 0) {
flowElem.className = "result-value positive-flow";
} else {
flowElem.className = "result-value negative-flow";
}
document.getElementById('resROI').innerText = roi.toFixed(2) + "%";
document.getElementById('resCapRate').innerText = capRate.toFixed(2) + "%";
document.getElementById('resMortgage').innerText = "$" + mortgagePayment.toFixed(2);
document.getElementById('resExpenses').innerText = "$" + totalExpensesWithMortgage.toFixed(2);
document.getElementById('resNOI').innerText = "$" + monthlyNOI.toFixed(2);
}
Understanding Rental Property Cash Flow
Investing in real estate is a powerful way to build wealth, but the success of a rental property largely depends on its math. A Rental Property Cash Flow Calculator is an essential tool for investors to evaluate whether a property will generate a profit (positive cash flow) or cost money to hold (negative cash flow).
What is Cash Flow?
Cash flow represents the net amount of cash moving into or out of an investment each month. In real estate terms, it is calculated as:
- Gross Income (Rent) minus Vacancy Losses minus Total Expenses (Mortgage, Taxes, Insurance, HOA, Repairs).
Positive cash flow means the property pays for itself and provides you with passive income. Negative cash flow means you must contribute your own money every month to keep the property running.
Key Metrics Explained
When using this calculator, pay close attention to these three metrics:
1. Cash on Cash ROI
This metric measures the return on the actual cash you invested (Down Payment). A Cash on Cash ROI of 8-12% is generally considered good for a long-term rental, while short-term rentals often target 15% or higher.
2. Cap Rate (Capitalization Rate)
Cap Rate measures the rate of return on the property based on its Net Operating Income (NOI), assuming the property was bought in cash (no mortgage). This helps you compare the profitability of different properties regardless of how they are financed.
3. Net Operating Income (NOI)
This is your total income minus operating expenses, excluding mortgage payments. It is a raw indicator of the property's efficiency in generating revenue.
How to Improve Cash Flow
If your calculation shows negative cash flow, consider these adjustments:
- Increase Rent: Are you charging market rates? Small increases can significantly impact the bottom line.
- Lower Expenses: Shop for cheaper insurance or handle minor maintenance tasks yourself.
- Larger Down Payment: Putting more money down reduces your monthly mortgage payment, instantly boosting cash flow (though it may lower your Cash on Cash ROI).
Use this calculator to run different scenarios before making an offer. Successful investors rarely buy on emotion; they buy based on the numbers.