Please check your inputs. Values must be positive numbers.
Monthly Principal & Interest:$0.00
Total Monthly Expenses:$0.00
Net Operating Income (NOI) / Month:$0.00
Monthly Cash Flow:$0.00
Cash on Cash Return (Annual):0.00%
Cap Rate:0.00%
Understanding Rental Property Cash Flow
Investing in real estate is one of the most reliable ways to build wealth, but simply buying a property doesn't guarantee profit. A robust Rental Property Cash Flow Calculator is essential for investors to analyze the potential profitability of a real estate asset before signing on the dotted line.
What is Cash Flow?
Cash flow is the net amount of cash moving into and out of a business. 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 provides passive income, while negative cash flow means the property is costing you money every month.
Key Metrics Calculated
Net Operating Income (NOI): This is your annual income minus all operating expenses, but excluding mortgage payments. It is a pure measure of the property's ability to generate revenue.
Cash on Cash Return (CoC): This metric measures the annual return the investor made on the property in relation to the amount of mortgage paid during the same year. It is calculated by dividing annual pre-tax cash flow by the total cash invested (down payment).
Cap Rate (Capitalization Rate): Calculated by dividing the NOI by the property's purchase price. It helps compare the profitability of similar properties regardless of how they are financed.
Estimating Expenses Accurately
Many new investors fail because they underestimate expenses. Beyond the mortgage, you must account for:
Vacancy: Properties won't be rented 365 days a year. A standard vacancy rate to budget for is 5-8%.
Maintenance: Roofs leak and toilets break. Setting aside 10-15% of rent for maintenance ensures you aren't caught off guard.
Property Management: If you don't plan to be a landlord yourself, expect to pay 8-10% of monthly rent to a management company.
How to Use This Calculator
Enter the purchase price, your financing details, and your estimated rental income. Be conservative with your estimates. If the calculator shows a positive Cash on Cash return using conservative numbers, you likely have a solid investment opportunity.
function calculateRental() {
// 1. Get Inputs
var price = parseFloat(document.getElementById('propPrice').value);
var downPercent = parseFloat(document.getElementById('downPaymentPercent').value);
var rate = parseFloat(document.getElementById('interestRate').value);
var term = parseFloat(document.getElementById('loanTerm').value);
var rent = parseFloat(document.getElementById('monthlyRent').value);
var vacancyRate = parseFloat(document.getElementById('vacancyRate').value);
var annualTax = parseFloat(document.getElementById('annualTax').value);
var annualIns = parseFloat(document.getElementById('annualInsurance').value);
var maintPercent = parseFloat(document.getElementById('maintenancePercent').value);
var mgmtPercent = parseFloat(document.getElementById('mgmtFee').value);
var errorDiv = document.getElementById('errorMsg');
var resultsDiv = document.getElementById('resultsArea');
// 2. Validation
if (isNaN(price) || isNaN(rent) || price 0) {
cashOnCash = (annualCashFlow / downPayment) * 100;
}
// 4. Output Display
document.getElementById('resMortgage').innerText = '$' + monthlyPI.toLocaleString('en-US', {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById('resExpenses').innerText = '$' + totalExpensesWithMortgage.toLocaleString('en-US', {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById('resNOI').innerText = '$' + monthlyNOI.toLocaleString('en-US', {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById('resCashFlow').innerText = '$' + monthlyCashFlow.toLocaleString('en-US', {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById('resCoC').innerText = cashOnCash.toLocaleString('en-US', {minimumFractionDigits: 2, maximumFractionDigits: 2}) + '%';
document.getElementById('resCapRate').innerText = capRate.toLocaleString('en-US', {minimumFractionDigits: 2, maximumFractionDigits: 2}) + '%';
// Show results
resultsDiv.style.display = 'block';
}