.rental-calculator-container {
font-family: 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
max-width: 800px;
margin: 0 auto;
background: #ffffff;
padding: 20px;
border-radius: 8px;
box-shadow: 0 4px 15px rgba(0,0,0,0.05);
color: #333;
}
.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 {
margin-bottom: 15px;
}
.input-group label {
display: block;
margin-bottom: 5px;
font-weight: 600;
font-size: 0.9em;
color: #555;
}
.input-group input, .input-group select {
width: 100%;
padding: 10px;
border: 1px solid #ddd;
border-radius: 4px;
font-size: 16px;
box-sizing: border-box;
}
.input-group input:focus {
border-color: #2c7a7b;
outline: none;
box-shadow: 0 0 0 2px rgba(44, 122, 123, 0.2);
}
.calc-btn {
background-color: #2c7a7b;
color: white;
border: none;
padding: 15px 30px;
font-size: 18px;
font-weight: bold;
border-radius: 6px;
cursor: pointer;
width: 100%;
transition: background-color 0.2s;
margin-bottom: 25px;
}
.calc-btn:hover {
background-color: #235c5d;
}
.results-box {
background-color: #f7fafc;
border: 1px solid #e2e8f0;
border-radius: 6px;
padding: 20px;
}
.result-row {
display: flex;
justify-content: space-between;
padding: 10px 0;
border-bottom: 1px solid #edf2f7;
}
.result-row:last-child {
border-bottom: none;
}
.result-label {
color: #4a5568;
}
.result-value {
font-weight: 700;
color: #2d3748;
}
.highlight-result {
color: #2c7a7b;
font-size: 1.2em;
}
.negative-flow {
color: #e53e3e;
}
.positive-flow {
color: #38a169;
}
.calc-article {
margin-top: 40px;
line-height: 1.6;
}
.calc-article h2 {
color: #2d3748;
border-bottom: 2px solid #2c7a7b;
padding-bottom: 10px;
margin-top: 30px;
}
.calc-article h3 {
color: #4a5568;
margin-top: 20px;
}
.calc-article p {
margin-bottom: 15px;
color: #4a5568;
}
.calc-article ul {
margin-bottom: 15px;
padding-left: 20px;
}
.calc-article li {
margin-bottom: 8px;
color: #4a5568;
}
function calculateRental() {
// Get Inputs
var price = parseFloat(document.getElementById('propPrice').value);
var downPerc = parseFloat(document.getElementById('downPaymentPerc').value);
var rate = parseFloat(document.getElementById('interestRate').value);
var termYears = parseFloat(document.getElementById('loanTerm').value);
var closingCosts = parseFloat(document.getElementById('closingCosts').value);
var rent = parseFloat(document.getElementById('monthlyRent').value);
var taxAnnual = parseFloat(document.getElementById('propTax').value);
var insAnnual = parseFloat(document.getElementById('insurance').value);
var hoa = parseFloat(document.getElementById('hoa').value);
var maintenance = parseFloat(document.getElementById('maintenance').value);
// Validation
if (isNaN(price) || isNaN(downPerc) || isNaN(rate) || isNaN(termYears) || isNaN(rent)) {
alert("Please enter valid numbers for all required fields.");
return;
}
// Calculations
var downPaymentAmt = price * (downPerc / 100);
var loanAmount = price – downPaymentAmt;
// Mortgage Calculation
var monthlyRate = rate / 100 / 12;
var numPayments = termYears * 12;
var monthlyMortgage = 0;
if (rate === 0) {
monthlyMortgage = loanAmount / numPayments;
} else {
monthlyMortgage = loanAmount * (monthlyRate * Math.pow(1 + monthlyRate, numPayments)) / (Math.pow(1 + monthlyRate, numPayments) – 1);
}
// Monthly Expense Breakdown
var monthlyTax = taxAnnual / 12;
var monthlyIns = insAnnual / 12;
var operatingExpenses = monthlyTax + monthlyIns + hoa + maintenance;
var totalMonthlyExpenses = operatingExpenses + monthlyMortgage;
// Cash Flow
var monthlyCashFlow = rent – totalMonthlyExpenses;
var annualCashFlow = monthlyCashFlow * 12;
// NOI (Net Operating Income) = Income – Operating Expenses (Excluding Debt Service)
var monthlyNOI = rent – operatingExpenses;
var annualNOI = monthlyNOI * 12;
// Returns
var totalCashInvested = downPaymentAmt + closingCosts;
var cocReturn = 0;
if (totalCashInvested > 0) {
cocReturn = (annualCashFlow / totalCashInvested) * 100;
}
var capRate = 0;
if (price > 0) {
capRate = (annualNOI / price) * 100;
}
// Display Results
document.getElementById('resultsArea').style.display = 'block';
// Format Currency
var formatter = new Intl.NumberFormat('en-US', {
style: 'currency',
currency: 'USD',
});
document.getElementById('resMortgage').innerText = formatter.format(monthlyMortgage);
document.getElementById('resExpenses').innerText = formatter.format(totalMonthlyExpenses); // Includes mortgage
document.getElementById('resNOI').innerText = formatter.format(monthlyNOI);
var cashFlowElem = document.getElementById('resCashFlow');
cashFlowElem.innerText = formatter.format(monthlyCashFlow);
// Styling positive/negative flow
if (monthlyCashFlow >= 0) {
cashFlowElem.classList.remove('negative-flow');
cashFlowElem.classList.add('positive-flow');
} else {
cashFlowElem.classList.remove('positive-flow');
cashFlowElem.classList.add('negative-flow');
}
document.getElementById('resCoC').innerText = cocReturn.toFixed(2) + "%";
document.getElementById('resCapRate').innerText = capRate.toFixed(2) + "%";
}
Rental Property Cash Flow Calculator
Purchase & Loan
30 Years
15 Years
10 Years
Income & Expenses
Monthly Mortgage (P&I):
$0.00
Total Monthly Expenses:
$0.00
Net Operating Income (Monthly):
$0.00
Monthly Cash Flow:
$0.00
Cash on Cash Return:
0.00%
Cap Rate:
0.00%
How to Analyze Rental Property Deals
Investing in real estate is one of the most reliable ways to build wealth, but it relies heavily on the numbers. A beautiful property is a bad investment if it drains your bank account every month. This Rental Property Cash Flow Calculator is designed to help investors quickly evaluate the profitability of a potential purchase.
Understanding Key Metrics
To make an informed decision, you need to understand three critical numbers calculated by this tool:
- Monthly Cash Flow: This is the net profit you pocket every month after all bills are paid. It is calculated as Rental Income – (Mortgage + Taxes + Insurance + HOA + Maintenance). A positive cash flow ensures the property pays for itself.
- Cash on Cash Return (CoC): This measures the return on the actual cash you invested (Down Payment + Closing Costs). It tells you how hard your money is working. A CoC of 8-12% is generally considered a solid benchmark for rentals.
- Cap Rate (Capitalization Rate): This metric evaluates the profitability of the property independent of financing. It is calculated by dividing the Net Operating Income (NOI) by the purchase price. It allows you to compare properties with different price points directly.
Common Expenses Often Overlooked
Many new investors fail because they underestimate expenses. When using this calculator, ensure you account for:
- Vacancy Rates: Properties won't be rented 100% of the time. It's wise to set aside 5-8% of rent for vacancy.
- CapEx (Capital Expenditures): Roofs, HVAC systems, and water heaters eventually need replacing. Allocating a monthly "Maintenance" budget buffers you against these large future costs.
- Property Management: Even if you plan to self-manage, analyzing the deal with a 10% management fee ensures the deal still works if you decide to hire a professional later.
How to Interpret the Results
If your Cash Flow is negative, the property is a liability, not an asset, unless you are banking purely on appreciation (a risky strategy). If your Cash on Cash Return is lower than the inflation rate or what you could get in the stock market, reconsider the purchase price or find ways to increase rental income.