.calculator-container {
max-width: 800px;
margin: 0 auto;
font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
color: #333;
background: #ffffff;
border: 1px solid #e0e0e0;
border-radius: 8px;
padding: 30px;
box-shadow: 0 4px 6px rgba(0,0,0,0.05);
}
.calc-header {
text-align: center;
margin-bottom: 30px;
}
.calc-header h2 {
margin: 0;
color: #2c3e50;
font-size: 28px;
}
.calc-header p {
color: #7f8c8d;
font-size: 16px;
}
.calc-grid {
display: grid;
grid-template-columns: 1fr 1fr;
gap: 20px;
margin-bottom: 25px;
}
@media (max-width: 600px) {
.calc-grid {
grid-template-columns: 1fr;
}
}
.input-group {
display: flex;
flex-direction: column;
}
.input-group label {
font-weight: 600;
margin-bottom: 8px;
font-size: 14px;
color: #34495e;
}
.input-group input {
padding: 12px;
border: 1px solid #bdc3c7;
border-radius: 4px;
font-size: 16px;
transition: border-color 0.3s;
}
.input-group input:focus {
border-color: #3498db;
outline: none;
}
.calc-btn {
width: 100%;
background-color: #27ae60;
color: white;
border: none;
padding: 15px;
font-size: 18px;
font-weight: bold;
border-radius: 4px;
cursor: pointer;
transition: background-color 0.3s;
margin-top: 10px;
}
.calc-btn:hover {
background-color: #219150;
}
.results-section {
margin-top: 30px;
background-color: #f8f9fa;
padding: 20px;
border-radius: 6px;
border-left: 5px solid #27ae60;
display: none;
}
.result-row {
display: flex;
justify-content: space-between;
align-items: center;
padding: 10px 0;
border-bottom: 1px solid #e9ecef;
}
.result-row:last-child {
border-bottom: none;
}
.result-label {
font-weight: 500;
color: #555;
}
.result-value {
font-weight: 700;
font-size: 18px;
color: #2c3e50;
}
.highlight-result {
color: #27ae60;
font-size: 22px;
}
.calc-article {
margin-top: 50px;
line-height: 1.6;
}
.calc-article h2 {
color: #2c3e50;
margin-top: 30px;
font-size: 24px;
}
.calc-article h3 {
color: #34495e;
font-size: 20px;
margin-top: 20px;
}
.calc-article p {
margin-bottom: 15px;
color: #444;
}
.calc-article ul {
margin-bottom: 20px;
padding-left: 20px;
}
.calc-article li {
margin-bottom: 10px;
color: #444;
}
function calculateCashFlow() {
// 1. Get Input Values
var price = parseFloat(document.getElementById('rp_price').value);
var downPercent = parseFloat(document.getElementById('rp_down').value);
var interestRate = parseFloat(document.getElementById('rp_rate').value);
var termYears = parseFloat(document.getElementById('rp_term').value);
var monthlyRent = parseFloat(document.getElementById('rp_rent').value);
var vacancyRate = parseFloat(document.getElementById('rp_vacancy').value);
var annualTax = parseFloat(document.getElementById('rp_tax').value);
var annualInsurance = parseFloat(document.getElementById('rp_insurance').value);
var monthlyHOA = parseFloat(document.getElementById('rp_hoa').value);
// Validation
if (isNaN(price) || isNaN(downPercent) || isNaN(interestRate) || isNaN(termYears)) {
alert("Please enter valid numbers for Price, Down Payment, Interest Rate, and Term.");
return;
}
// 2. Calculate Mortgage (Principal & Interest)
var downPaymentAmount = price * (downPercent / 100);
var loanAmount = price – downPaymentAmount;
var monthlyRate = (interestRate / 100) / 12;
var numberOfPayments = termYears * 12;
var mortgagePayment = 0;
if (interestRate === 0) {
mortgagePayment = loanAmount / numberOfPayments;
} else {
mortgagePayment = loanAmount * (monthlyRate * Math.pow(1 + monthlyRate, numberOfPayments)) / (Math.pow(1 + monthlyRate, numberOfPayments) – 1);
}
// 3. Calculate Monthly Expenses
var monthlyTax = annualTax / 12;
var monthlyInsurance = annualInsurance / 12;
var monthlyVacancyAndMaint = monthlyRent * (vacancyRate / 100);
// Handling NaNs for optional fields
if (isNaN(monthlyHOA)) monthlyHOA = 0;
if (isNaN(monthlyVacancyAndMaint)) monthlyVacancyAndMaint = 0;
if (isNaN(monthlyTax)) monthlyTax = 0;
if (isNaN(monthlyInsurance)) monthlyInsurance = 0;
var totalMonthlyExpenses = mortgagePayment + monthlyTax + monthlyInsurance + monthlyHOA + monthlyVacancyAndMaint;
// 4. Calculate Results
var netMonthlyCashFlow = monthlyRent – totalMonthlyExpenses;
var annualCashFlow = netMonthlyCashFlow * 12;
// Cash on Cash Return = Annual Cash Flow / Total Cash Invested
// Assuming Total Cash Invested is primarily the Down Payment for this simple calc
var cashOnCashReturn = 0;
if (downPaymentAmount > 0) {
cashOnCashReturn = (annualCashFlow / downPaymentAmount) * 100;
}
// 5. Display Results
// Formatting to Currency
var formatter = new Intl.NumberFormat('en-US', {
style: 'currency',
currency: 'USD',
});
document.getElementById('res_mortgage').innerText = formatter.format(mortgagePayment);
document.getElementById('res_expenses').innerText = formatter.format(totalMonthlyExpenses);
var cashFlowEl = document.getElementById('res_cashflow');
cashFlowEl.innerText = formatter.format(netMonthlyCashFlow);
// Style adjustments for positive/negative cash flow
if (netMonthlyCashFlow >= 0) {
cashFlowEl.style.color = "#27ae60";
} else {
cashFlowEl.style.color = "#c0392b";
}
document.getElementById('res_coc').innerText = cashOnCashReturn.toFixed(2) + "%";
// Show result section
document.getElementById('rp_results').style.display = 'block';
}
Rental Property Cash Flow Calculator
Analyze the profitability of your real estate investment instantly.
Monthly Principal & Interest:
$0.00
Total Monthly Expenses:
$0.00
Net Monthly Cash Flow:
$0.00
Cash on Cash Return:
0.00%
Understanding Rental Property Cash Flow
Investing in rental real estate is one of the most reliable ways to build long-term wealth, but not every property is a good deal. The Rental Property Cash Flow Calculator helps investors determine if a specific property will generate profit (positive cash flow) or cost money to hold (negative cash flow).
What is Cash Flow?
Cash flow is the net amount of cash moving in and out of an investment. In real estate, it is calculated as:
- Gross Income: Total rent collected plus any other income (laundry, parking).
- Operating Expenses: Taxes, insurance, HOA fees, maintenance, and vacancy reserves.
- Debt Service: The principal and interest payments on your mortgage.
A positive cash flow means the property pays for itself and puts money in your pocket every month.
Why Cash on Cash (CoC) Return Matters
While cash flow tells you the dollar amount you earn, the Cash on Cash Return tells you how hard your money is working. It measures the annual pre-tax cash flow divided by the total cash invested (down payment, closing costs, and rehab costs).
For example, if you invest $50,000 to buy a house and it generates $5,000 in positive cash flow per year, your CoC return is 10%. This metric allows you to compare real estate returns against other investment vehicles like stocks or bonds.
How to Interpret the Results
- Positive Cash Flow: The property is self-sustaining. This is the goal for most buy-and-hold investors.
- Negative Cash Flow: The property costs you money every month. Investors might accept this if they are banking on high appreciation, but it is risky.
- Vacancy & Maintenance: Always budget for these! Our calculator defaults to 10%, which is a safe baseline for repairs and periods without tenants.