.calc-row { display: flex; flex-wrap: wrap; margin-bottom: 15px; justify-content: space-between; }
.calc-col { flex: 1 1 45%; margin-right: 10px; min-width: 250px; margin-bottom: 10px; }
.calc-col:last-child { margin-right: 0; }
.calc-label { display: block; margin-bottom: 5px; font-weight: bold; color: #333; }
.calc-input { width: 100%; padding: 10px; border: 1px solid #ccc; border-radius: 4px; box-sizing: border-box; }
.calc-btn { width: 100%; padding: 12px; background-color: #2c7a3f; color: white; border: none; border-radius: 4px; cursor: pointer; font-size: 16px; font-weight: bold; transition: background 0.3s; }
.calc-btn:hover { background-color: #1e5c2e; }
.result-box { margin-top: 25px; padding: 20px; background-color: #fff; border: 1px solid #ddd; border-radius: 4px; border-left: 5px solid #2c7a3f; display: none; }
.result-row { display: flex; justify-content: space-between; margin-bottom: 10px; border-bottom: 1px solid #eee; padding-bottom: 5px; }
.result-row:last-child { border-bottom: none; }
.result-label { color: #555; }
.result-value { font-weight: bold; color: #333; }
.highlight-result { font-size: 1.2em; color: #2c7a3f; }
.error-msg { color: red; display: none; margin-bottom: 10px; }
h2.calc-title { text-align: center; color: #2c7a3f; margin-bottom: 20px; }
function calculateRentalCashFlow() {
// Get inputs
var price = parseFloat(document.getElementById('purchasePrice').value);
var downPercent = parseFloat(document.getElementById('downPayment').value);
var rate = parseFloat(document.getElementById('interestRate').value);
var term = parseFloat(document.getElementById('loanTerm').value);
var rent = parseFloat(document.getElementById('monthlyRent').value);
var vacancy = parseFloat(document.getElementById('vacancyRate').value);
var tax = parseFloat(document.getElementById('propertyTax').value);
var insurance = parseFloat(document.getElementById('insurance').value);
var hoa = parseFloat(document.getElementById('hoaFees').value);
var maint = parseFloat(document.getElementById('maintenance').value);
// Error handling
var errorDiv = document.getElementById('calcError');
if (isNaN(price) || isNaN(downPercent) || isNaN(rate) || isNaN(term) || isNaN(rent) || isNaN(tax) || isNaN(insurance)) {
errorDiv.style.display = 'block';
document.getElementById('rentalResult').style.display = 'none';
return;
}
errorDiv.style.display = 'none';
// Calculations
var downAmount = price * (downPercent / 100);
var loanAmount = price – downAmount;
// Mortgage Calculation (Monthly P&I)
var monthlyRate = rate / 100 / 12;
var numPayments = term * 12;
var mortgage = 0;
if (rate === 0) {
mortgage = loanAmount / numPayments;
} else {
mortgage = (loanAmount * monthlyRate) / (1 – Math.pow(1 + monthlyRate, -numPayments));
}
// Monthly Expense Breakdown
var monthlyTax = tax / 12;
var monthlyIns = insurance / 12;
var vacancyCost = rent * (vacancy / 100);
var maintCost = rent * (maint / 100);
// Total Monthly Operating Expenses (excluding mortgage)
var operatingExpenses = monthlyTax + monthlyIns + hoa + vacancyCost + maintCost;
// Total Outflow
var totalOutflow = mortgage + operatingExpenses;
// Cash Flow
var cashFlow = rent – totalOutflow;
// Annual Cash Flow & Cash on Cash Return
var annualCashFlow = cashFlow * 12;
// Assuming closing costs are roughly 2% of price for simplicity in CoC, or just using downpayment as base equity
// Standard simple CoC = Annual Cash Flow / Total Cash Invested (Down Payment)
var cocReturn = (annualCashFlow / downAmount) * 100;
// Display Results
var formatter = new Intl.NumberFormat('en-US', { style: 'currency', currency: 'USD' });
document.getElementById('resIncome').innerText = formatter.format(rent);
document.getElementById('resMortgage').innerText = formatter.format(mortgage);
document.getElementById('resExpenses').innerText = formatter.format(operatingExpenses);
document.getElementById('resTotalOut').innerText = formatter.format(totalOutflow);
var cashFlowElem = document.getElementById('resCashFlow');
cashFlowElem.innerText = formatter.format(cashFlow);
cashFlowElem.style.color = cashFlow >= 0 ? '#2c7a3f' : '#d32f2f';
document.getElementById('resCoc').innerText = cocReturn.toFixed(2) + "%";
document.getElementById('rentalResult').style.display = 'block';
}
Rental Property Cash Flow Calculator
Please enter valid numeric values for all fields.
Monthly Financial Summary
Gross Income:
Mortgage Payment (P&I):
Operating Expenses (Tax, Ins, Maint, Vacancy):
Total Monthly Outflow:
Net Monthly Cash Flow:
Cash on Cash Return (CoC):
Understanding Rental Property Cash Flow
Calculating cash flow is the fundamental step in evaluating any real estate investment. It determines whether a rental property is an asset that puts money in your pocket every month or a liability that drains your resources. This Rental Property Cash Flow Calculator helps investors accurately predict the profitability of a potential purchase by factoring in income, mortgage obligations, and variable operating expenses.
What is Positive Cash Flow?
Positive cash flow occurs when your property's gross monthly rental income exceeds all associated expenses, including principal, interest, taxes, insurance, and maintenance reserves. In contrast, negative cash flow implies you must contribute personal funds monthly to keep the property running, which is generally risky for long-term investors.
Key Metrics Explained
When using this calculator, it is crucial to understand the input variables to get an accurate result:
- Vacancy Rate: No property is occupied 100% of the time. A standard conservative estimate is 5% to 8%, representing the income lost while finding new tenants.
- Maintenance & CapEx: Even if the house is new, you must set aside a percentage of rent (typically 5-10%) for future repairs like water heaters, roofs, or painting.
- Cash on Cash Return (CoC): This metric measures the annual return on the actual cash you invested (down payment). It is calculated as (Annual Cash Flow / Total Cash Invested) x 100. A CoC return of 8-12% is often considered a solid benchmark for residential real estate.
Why Use a Cash Flow Calculator?
Many novice investors make the mistake of only subtracting the mortgage payment from the rent to determine profit. This "napkin math" ignores significant costs like vacancy, property management (if applicable), HOA fees, and taxes. By using a comprehensive calculator, you account for the hidden costs of ownership, ensuring your investment strategy is based on data, not just optimism.