Analyze your potential real estate investment returns.
Please enter valid numeric values for all fields.
Investment Analysis
Monthly Cash Flow:$0.00
Net Operating Income (Monthly):$0.00
Total Monthly Expenses:$0.00
Cash on Cash Return (CoC):0.00%
Cap Rate:0.00%
function calculateCashFlow() {
// 1. Get Input Values
var price = parseFloat(document.getElementById('rpc_price').value);
var downPercent = parseFloat(document.getElementById('rpc_down').value);
var interestRate = parseFloat(document.getElementById('rpc_rate').value);
var termYears = parseFloat(document.getElementById('rpc_term').value);
var rent = parseFloat(document.getElementById('rpc_rent').value);
var vacancyPercent = parseFloat(document.getElementById('rpc_vacancy').value);
var annualTax = parseFloat(document.getElementById('rpc_tax').value);
var annualIns = parseFloat(document.getElementById('rpc_insurance').value);
var monthlyMaint = parseFloat(document.getElementById('rpc_maint').value);
var monthlyHOA = parseFloat(document.getElementById('rpc_hoa').value);
var errorMsg = document.getElementById('rpc_error_msg');
var resultsDiv = document.getElementById('rpc_results');
// 2. Validation
if (isNaN(price) || isNaN(downPercent) || isNaN(interestRate) || isNaN(termYears) ||
isNaN(rent) || isNaN(vacancyPercent) || isNaN(annualTax) || isNaN(annualIns) ||
isNaN(monthlyMaint) || isNaN(monthlyHOA)) {
errorMsg.style.display = 'block';
resultsDiv.classList.remove('visible');
return;
}
errorMsg.style.display = 'none';
// 3. Calculation Logic
// Loan Calculations
var downPaymentAmount = price * (downPercent / 100);
var loanAmount = price – downPaymentAmount;
var monthlyRate = (interestRate / 100) / 12;
var numberOfPayments = termYears * 12;
// Mortgage Payment Formula: M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1]
var monthlyMortgage = 0;
if (monthlyRate > 0) {
monthlyMortgage = loanAmount * (monthlyRate * Math.pow(1 + monthlyRate, numberOfPayments)) / (Math.pow(1 + monthlyRate, numberOfPayments) – 1);
} else {
monthlyMortgage = loanAmount / numberOfPayments;
}
// Income Calculations
var vacancyLoss = rent * (vacancyPercent / 100);
var effectiveGrossIncome = rent – vacancyLoss;
// Expense Calculations (Monthly)
var monthlyTax = annualTax / 12;
var monthlyIns = annualIns / 12;
var operatingExpenses = monthlyTax + monthlyIns + monthlyMaint + monthlyHOA;
var totalExpenses = operatingExpenses + monthlyMortgage;
// Metric Calculations
var monthlyNOI = effectiveGrossIncome – operatingExpenses;
var monthlyCashFlow = effectiveGrossIncome – totalExpenses;
var annualCashFlow = monthlyCashFlow * 12;
var annualNOI = monthlyNOI * 12;
// ROI Metrics
// Cash on Cash = Annual Pre-Tax Cash Flow / Total Cash Invested
// For simplicity, assuming Total Cash Invested = Down Payment (users can estimate closing costs in down payment if they wish, or we keep it simple)
var cashInvested = downPaymentAmount;
var cashOnCash = 0;
if (cashInvested > 0) {
cashOnCash = (annualCashFlow / cashInvested) * 100;
}
// Cap Rate = Annual NOI / Purchase Price
var capRate = (annualNOI / price) * 100;
// 4. Update UI
document.getElementById('res_cashflow').innerHTML = formatCurrency(monthlyCashFlow);
document.getElementById('res_noi').innerHTML = formatCurrency(monthlyNOI);
document.getElementById('res_expenses').innerHTML = formatCurrency(totalExpenses);
// Color coding for cash flow
if (monthlyCashFlow >= 0) {
document.getElementById('res_cashflow').style.color = "#27ae60";
} else {
document.getElementById('res_cashflow').style.color = "#e74c3c";
}
document.getElementById('res_coc').innerHTML = cashOnCash.toFixed(2) + "%";
document.getElementById('res_cap').innerHTML = capRate.toFixed(2) + "%";
// Show results
resultsDiv.classList.add('visible');
}
function formatCurrency(num) {
return "$" + num.toFixed(2).replace(/\d(?=(\d{3})+\.)/g, '$&,');
}
Understanding Rental Property Cash Flow Analysis
Investing in real estate is one of the most reliable ways to build long-term wealth, but success hinges on the numbers. A Rental Property Cash Flow Calculator is an essential tool for investors to evaluate the profitability of a potential purchase before signing any contracts. By breaking down income, operating expenses, and financing costs, you can determine if a property will generate passive income or become a financial drain.
What is Positive Cash Flow?
Cash flow is the net amount of money moving in and out of a business or investment. In real estate, positive cash flow occurs when a property's gross income (rent) exceeds all expenses, including the mortgage, taxes, insurance, and maintenance. Positive cash flow is crucial because it provides a safety net against vacancies and unexpected repairs while putting money in your pocket every month.
Conversely, negative cash flow implies you are losing money every month to hold the property. While some investors accept negative cash flow in hopes of high appreciation, it is generally considered a higher-risk strategy.
Key Metrics Explained
Our calculator provides several critical metrics to help you assess a deal:
NOI (Net Operating Income): This is your annual income minus operating expenses, excluding mortgage payments. It measures the profitability of the property itself, regardless of financing.
Cash on Cash Return (CoC): This is arguably the most important metric for ROI. It measures the annual cash flow relative to the total cash invested (down payment). A CoC return of 8-12% is often considered a solid target for rental investors.
Cap Rate (Capitalization Rate): Calculated as NOI divided by the purchase price. Cap rate helps compare the profitability of different properties irrespective of how they are financed. Higher cap rates generally indicate higher returns but may come with higher risks (e.g., properties in less desirable neighborhoods).
How to Estimate Expenses accurately
One of the biggest mistakes new investors make is underestimating expenses. When using the calculator, ensure you account for:
Vacancy Rate: No property is occupied 100% of the time. A standard conservative estimate is 5-8% (about 2-3 weeks of vacancy per year).
Maintenance & Repairs: Budgeting 1% of the property value per year, or 10-15% of the rent, is a prudent way to prepare for leaky faucets, HVAC repairs, and turnover costs.
Management Fees: Even if you plan to self-manage, it is wise to factor in a management fee (typically 8-10% of rent) to ensure the deal still works if you decide to hire a professional later.
The 1% Rule
A common rule of thumb for initial screening is the 1% Rule. This rule suggests that the monthly rent should be at least 1% of the purchase price. For example, a $200,000 home should rent for at least $2,000 per month. While this rule is becoming harder to meet in expensive markets, it remains a useful quick-check filter before running a detailed analysis with the calculator above.
Use this calculator to adjust your offer price, down payment, or rental expectations to find a deal that meets your financial goals.