Analyze your real estate investment deal in seconds.
1. Purchase & Loan Information
30 Years
15 Years
10 Years
2. Rental Income
3. Operating Expenses
Monthly Cash Flow
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Cash on Cash ROI
0.00%
Cap Rate
0.00%
Monthly Expenses
$0.00
Mortgage Payment
$0.00
Total Cash Invested
$0.00
function calculateRental() {
// 1. Get Input Values
var purchasePrice = parseFloat(document.getElementById("purchasePrice").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) || 30;
var closingCosts = parseFloat(document.getElementById("closingCosts").value) || 0;
var monthlyRent = parseFloat(document.getElementById("monthlyRent").value) || 0;
var otherIncome = parseFloat(document.getElementById("otherIncome").value) || 0;
var annualTaxes = parseFloat(document.getElementById("annualTaxes").value) || 0;
var annualInsurance = parseFloat(document.getElementById("annualInsurance").value) || 0;
var monthlyHOA = parseFloat(document.getElementById("monthlyHOA").value) || 0;
var monthlyMaintenance = parseFloat(document.getElementById("monthlyMaintenance").value) || 0;
var propertyManagementPercent = parseFloat(document.getElementById("propertyManagement").value) || 0;
// 2. Perform Calculations
// Loan Calculation
var downPaymentAmount = purchasePrice * (downPaymentPercent / 100);
var loanAmount = purchasePrice – downPaymentAmount;
var monthlyRate = (interestRate / 100) / 12;
var totalPayments = loanTerm * 12;
var monthlyMortgage = 0;
if (loanAmount > 0 && interestRate > 0) {
monthlyMortgage = (loanAmount * monthlyRate) / (1 – Math.pow(1 + monthlyRate, -totalPayments));
} else if (loanAmount > 0 && interestRate === 0) {
monthlyMortgage = loanAmount / totalPayments;
}
// Income Calculation
var totalMonthlyIncome = monthlyRent + otherIncome;
// Expense Calculation
var managementFee = totalMonthlyIncome * (propertyManagementPercent / 100);
var totalMonthlyOperatingExpenses = (annualTaxes / 12) + (annualInsurance / 12) + monthlyHOA + monthlyMaintenance + managementFee;
var totalMonthlyExpenses = totalMonthlyOperatingExpenses + monthlyMortgage;
// Profitability Metrics
var monthlyCashFlow = totalMonthlyIncome – totalMonthlyExpenses;
var annualCashFlow = monthlyCashFlow * 12;
var totalCashInvested = downPaymentAmount + closingCosts;
// Net Operating Income (NOI) = Income – Operating Expenses (excludes mortgage)
var annualNOI = (totalMonthlyIncome * 12) – (totalMonthlyOperatingExpenses * 12);
// ROI Metrics
var cashOnCash = 0;
if (totalCashInvested > 0) {
cashOnCash = (annualCashFlow / totalCashInvested) * 100;
}
var capRate = 0;
if (purchasePrice > 0) {
capRate = (annualNOI / purchasePrice) * 100;
}
// 3. Display Results
document.getElementById("resultCashFlow").innerText = formatMoney(monthlyCashFlow);
document.getElementById("resultCoC").innerText = cashOnCash.toFixed(2) + "%";
document.getElementById("resultCapRate").innerText = capRate.toFixed(2) + "%";
document.getElementById("resultExpenses").innerText = formatMoney(totalMonthlyExpenses);
document.getElementById("resultMortgage").innerText = formatMoney(monthlyMortgage);
document.getElementById("resultInvested").innerText = formatMoney(totalCashInvested);
// Styling for positive/negative cash flow
var cashFlowContainer = document.getElementById("cashFlowMetric");
if (monthlyCashFlow >= 0) {
cashFlowContainer.className = "rpc-metric highlight";
document.getElementById("resultCashFlow").style.color = "#27ae60";
} else {
cashFlowContainer.className = "rpc-metric highlight-neg";
document.getElementById("resultCashFlow").style.color = "#c0392b";
}
// Show result container
document.getElementById("rpcResultContainer").style.display = "grid";
document.getElementById("rpcResultContainer").className = "rpc-results active";
}
function formatMoney(amount) {
return "$" + amount.toFixed(2).replace(/\d(?=(\d{3})+\.)/g, '$&,');
}
Why Use a Rental Property Cash Flow Calculator?
Successful real estate investing hinges on one critical metric: Cash Flow. Simply put, cash flow is the net income from a real estate investment after mortgage payments and operating expenses have been made. A positive cash flow means your property is generating income for you every month, while a negative cash flow means you are losing money to hold the asset.
Using our Rental Property Cash Flow Calculator helps investors analyze deals objectively rather than emotionally. By inputting concrete data regarding purchase price, loan terms, and anticipated expenses, you can determine if a property fits your investment criteria before making an offer.
Key Metrics Explained
Cash on Cash Return (CoC): This measures the annual return on the actual cash you invested (down payment + closing costs). It is one of the most important metrics because it tells you how hard your money is working. A CoC of 10% means you earn back 10% of your invested capital per year.
Cap Rate (Capitalization Rate): This measures the property's natural rate of return without factoring in the mortgage. It is calculated by dividing the Net Operating Income (NOI) by the property value. It helps compare properties irrespective of financing methods.
Net Operating Income (NOI): The total income minus operating expenses. This excludes your mortgage payment (debt service) and income taxes.
How to Calculate Rental Property Cash Flow
The formula for calculating cash flow is relatively straightforward, though getting accurate inputs is the challenge:
Operating expenses typically include property management fees, maintenance reserves, vacancy allowances, property taxes, insurance, and HOA fees. Debt service refers to your monthly principal and interest mortgage payments.
Frequently Asked Questions
What is a "good" cash flow per door?
Many investors aim for at least $100 to $200 in net positive cash flow per unit per month. However, this varies based on your strategy (appreciation vs. cash flow) and the market.
Should I include vacancy and maintenance in my calculation?
Absolutely. Even if the property is currently rented and in good condition, you will eventually have vacancy and repair costs. A common rule of thumb is to set aside 5-10% of rent for maintenance and 5-8% for vacancy.
How does the interest rate affect my cash flow?
Interest rates have a direct impact on your debt service. A higher interest rate increases your monthly mortgage payment, which directly reduces your net cash flow. This calculator allows you to test different rate scenarios to see how sensitive your deal is to rate changes.