Calculate NOI, Cap Rate, and Monthly Cash Flow for your real estate investment.
Purchase Information
Income Assumptions
Operating Expenses
Investment Performance
Monthly Cash Flow$0.00
Annual Cash Flow$0.00
Net Operating Income (NOI – Annual)$0.00
Cap Rate0.00%
Cash on Cash Return0.00%
Monthly Mortgage Payment (P&I)$0.00
Total Cash Needed to Close$0.00
function calculateCashFlow() {
// Get Input Values
var purchasePrice = parseFloat(document.getElementById('purchasePrice').value) || 0;
var closingCosts = parseFloat(document.getElementById('closingCosts').value) || 0;
var downPaymentPercent = parseFloat(document.getElementById('downPaymentPercent').value) || 0;
var interestRate = parseFloat(document.getElementById('interestRate').value) || 0;
var loanTerm = parseFloat(document.getElementById('loanTerm').value) || 0;
var monthlyRent = parseFloat(document.getElementById('monthlyRent').value) || 0;
var vacancyRate = parseFloat(document.getElementById('vacancyRate').value) || 0;
var propertyTaxAnnual = parseFloat(document.getElementById('propertyTax').value) || 0;
var insuranceAnnual = parseFloat(document.getElementById('insurance').value) || 0;
var hoaMonthly = parseFloat(document.getElementById('hoa').value) || 0;
var maintenancePercent = parseFloat(document.getElementById('maintenance').value) || 0;
var managementFeePercent = parseFloat(document.getElementById('managementFee').value) || 0;
var capexMonthly = parseFloat(document.getElementById('capex').value) || 0;
// Calculate Initial Investment
var downPaymentAmount = purchasePrice * (downPaymentPercent / 100);
var loanAmount = purchasePrice – downPaymentAmount;
var totalCashNeeded = downPaymentAmount + closingCosts;
// Calculate Mortgage (P&I)
var monthlyRate = (interestRate / 100) / 12;
var numPayments = loanTerm * 12;
var monthlyMortgage = 0;
if (interestRate > 0) {
monthlyMortgage = (loanAmount * monthlyRate * Math.pow(1 + monthlyRate, numPayments)) / (Math.pow(1 + monthlyRate, numPayments) – 1);
} else {
monthlyMortgage = loanAmount / numPayments;
}
// Calculate Income
var vacancyCost = monthlyRent * (vacancyRate / 100);
var effectiveGrossIncome = monthlyRent – vacancyCost;
// Calculate Monthly Expenses
var maintenanceCost = monthlyRent * (maintenancePercent / 100);
var managementCost = monthlyRent * (managementFeePercent / 100);
var taxMonthly = propertyTaxAnnual / 12;
var insuranceMonthly = insuranceAnnual / 12;
var totalOperatingExpenses = taxMonthly + insuranceMonthly + hoaMonthly + maintenanceCost + managementCost + capexMonthly;
// Net Operating Income (NOI)
var monthlyNOI = effectiveGrossIncome – totalOperatingExpenses;
var annualNOI = monthlyNOI * 12;
// Cash Flow
var monthlyCashFlow = monthlyNOI – monthlyMortgage;
var annualCashFlow = monthlyCashFlow * 12;
// Returns
var capRate = (annualNOI / purchasePrice) * 100;
var cashOnCash = (annualCashFlow / totalCashNeeded) * 100;
// Formatting Helpers
var formatCurrency = function(num) {
return '$' + num.toFixed(2).replace(/\d(?=(\d{3})+\.)/g, '$&,');
};
var formatPercent = function(num) {
return num.toFixed(2) + '%';
};
// Update UI
document.getElementById('monthlyCashFlow').innerHTML = formatCurrency(monthlyCashFlow);
if(monthlyCashFlow < 0) {
document.getElementById('monthlyCashFlow').classList.add('negative');
} else {
document.getElementById('monthlyCashFlow').classList.remove('negative');
}
document.getElementById('annualCashFlow').innerHTML = formatCurrency(annualCashFlow);
document.getElementById('annualNOI').innerHTML = formatCurrency(annualNOI);
document.getElementById('capRate').innerHTML = formatPercent(capRate);
document.getElementById('cashOnCash').innerHTML = formatPercent(cashOnCash);
document.getElementById('mortgagePayment').innerHTML = formatCurrency(monthlyMortgage);
document.getElementById('totalCashNeeded').innerHTML = formatCurrency(totalCashNeeded);
document.getElementById('results').style.display = 'block';
}
Understanding Your Rental Property Cash Flow
Investing in real estate is one of the most reliable ways to build wealth, but the difference between a successful investment and a financial burden often comes down to the numbers. A Rental Property Cash Flow Calculator is an essential tool for investors to evaluate whether a property will generate positive income after all expenses are paid.
What is Cash Flow in Real Estate?
Cash flow is the net amount of cash moving into and out of a business. In real estate, it represents the money remaining after you have collected rent and paid all operating expenses and debt service (mortgage payments). Positive cash flow means the property is putting money in your pocket every month, while negative cash flow means you are paying out of pocket to hold the asset.
Key Metrics Explained
Net Operating Income (NOI): This is the total income the property generates minus all necessary operating expenses (taxes, insurance, maintenance, management). Notably, NOI does not include mortgage payments. It measures the profitability of the property itself, regardless of financing.
Cap Rate (Capitalization Rate): Calculated as NOI / Purchase Price. The Cap Rate helps you compare the return on investment of different properties as if you bought them with all cash. A higher Cap Rate generally indicates a higher potential return, though often with higher risk.
Cash on Cash Return: This is arguably the most important metric for leveraged investors. It is calculated as Annual Cash Flow / Total Cash Invested. It tells you exactly how hard your actual invested dollars (down payment + closing costs) are working for you.
How to Use This Calculator
To get the most accurate results from this calculator, ensure you are accounting for all "hidden" costs of ownership:
Vacancy Rate: No property is occupied 100% of the time. A standard conservative estimate is 5% to 8% (representing about 2-4 weeks of vacancy per year).
Maintenance & CapEx: Even if the house is new, things break. Allocating 5-10% of rent for repairs ensures you have funds ready for a leaky faucet or a new roof.
Management Fees: If you hire a property manager, they typically charge 8-10% of the monthly rent. If you self-manage, you are trading your time for this fee.
Example Scenario
Imagine you purchase a property for $250,000 with 20% down ($50,000). You rent it out for $2,200/month.
After paying the mortgage (approx. $1,264 at 6.5%), taxes ($250/mo), insurance ($100/mo), and setting aside money for vacancy and repairs ($220/mo), your monthly expenses might total $1,834.
Your Monthly Cash Flow would be: $2,200 (Rent) – $1,834 (Total Outflow) = $366/month.
This positive cash flow protects you against market downturns and helps you save for your next investment property.