Analyze your real estate investment returns, cash flow, and cap rate.
Purchase & Loan Details
Income & Expenses
Monthly Mortgage P&I:$0.00
Total Monthly Expenses:$0.00
Monthly Net Operating Income (NOI):$0.00
Monthly Cash Flow:$0.00
Cash on Cash Return (ROI):0.00%
Cap Rate:0.00%
function calculateRental() {
// 1. Get Inputs
var price = parseFloat(document.getElementById('rpc_price').value) || 0;
var downPercent = parseFloat(document.getElementById('rpc_down_percent').value) || 0;
var rate = parseFloat(document.getElementById('rpc_rate').value) || 0;
var term = parseFloat(document.getElementById('rpc_term').value) || 0;
var closingCosts = parseFloat(document.getElementById('rpc_closing_costs').value) || 0;
var rent = parseFloat(document.getElementById('rpc_rent').value) || 0;
var taxYearly = parseFloat(document.getElementById('rpc_tax').value) || 0;
var insYearly = parseFloat(document.getElementById('rpc_insurance').value) || 0;
var hoaMonthly = parseFloat(document.getElementById('rpc_hoa').value) || 0;
var maintPercent = parseFloat(document.getElementById('rpc_maint').value) || 0;
var vacancyPercent = parseFloat(document.getElementById('rpc_vacancy').value) || 0;
// 2. Loan Calculations
var downPayment = price * (downPercent / 100);
var loanAmount = price – downPayment;
var monthlyRate = (rate / 100) / 12;
var numPayments = term * 12;
var mortgage = 0;
if (loanAmount > 0 && rate > 0) {
mortgage = (loanAmount * monthlyRate) / (1 – Math.pow(1 + monthlyRate, -numPayments));
} else if (loanAmount > 0 && rate === 0) {
mortgage = loanAmount / numPayments;
}
// 3. Operating Expense Calculations
var vacancyCost = rent * (vacancyPercent / 100);
var maintCost = rent * (maintPercent / 100);
var taxMonthly = taxYearly / 12;
var insMonthly = insYearly / 12;
var totalOpExpenses = taxMonthly + insMonthly + hoaMonthly + maintCost + vacancyCost;
var totalExpenses = totalOpExpenses + mortgage;
// 4. Income Metrics
var noiMonthly = (rent – vacancyCost) – (taxMonthly + insMonthly + hoaMonthly + maintCost);
var cashFlowMonthly = rent – totalExpenses;
var cashFlowYearly = cashFlowMonthly * 12;
var noiYearly = noiMonthly * 12;
// 5. ROI Calculations
var totalCashInvested = downPayment + closingCosts;
var cocReturn = 0;
if (totalCashInvested > 0) {
cocReturn = (cashFlowYearly / totalCashInvested) * 100;
}
var capRate = 0;
if (price > 0) {
capRate = (noiYearly / price) * 100;
}
// 6. Formatting Helper
var formatCurrency = function(num) {
return '$' + num.toFixed(2).replace(/\d(?=(\d{3})+\.)/g, '$&,');
};
// 7. Output Results
document.getElementById('res_mortgage').innerText = formatCurrency(mortgage);
document.getElementById('res_expenses').innerText = formatCurrency(totalExpenses);
document.getElementById('res_noi').innerText = formatCurrency(noiMonthly);
document.getElementById('res_cashflow').innerText = formatCurrency(cashFlowMonthly);
// Color code cash flow
var cfElem = document.getElementById('res_cashflow');
if (cashFlowMonthly >= 0) {
cfElem.style.color = "#27ae60";
} else {
cfElem.style.color = "#c0392b";
}
document.getElementById('res_coc').innerText = cocReturn.toFixed(2) + '%';
document.getElementById('res_cap').innerText = capRate.toFixed(2) + '%';
// Show result box
document.getElementById('rpc_results').style.display = 'block';
}
Understanding Rental Property Investment Metrics
Investing in real estate is one of the most reliable ways to build wealth, but it requires careful analysis to ensure a property will be profitable. This Rental Property Cash Flow Calculator helps investors evaluate the financial performance of a potential buy-and-hold asset.
1. Monthly Cash Flow
Cash flow is the profit you take home each month after paying all operating expenses and debt service (mortgage). A positive cash flow indicates a healthy investment that pays you to own it. Our calculator accounts for rent, taxes, insurance, HOA fees, vacancy rates, and maintenance reserves to give you a realistic "Net Monthly Income."
2. Cash on Cash Return (CoC ROI)
This is arguably the most important metric for rental investors. It measures the annual return on the actual cash you invested (Down Payment + Closing Costs), rather than the total price of the home.
Formula: (Annual Pre-Tax Cash Flow / Total Cash Invested) × 100%.
Generally, investors aim for a CoC return between 8% and 12% in steady markets.
3. Cap Rate (Capitalization Rate)
The Cap Rate measures the natural rate of return of the property assuming it was bought with all cash (no loan). It is calculated by dividing the Net Operating Income (NOI) by the purchase price. This helps you compare the profitability of different properties regardless of how they are financed.
Real-World Example
Let's assume you find a property listed for $250,000.
Investment: You put 20% down ($50,000) and pay $5,000 in closing costs. Total Cash Invested = $55,000.
Income: The property rents for $2,200/month.
Expenses: After mortgage, taxes, insurance, and setting aside money for repairs/vacancy, your total monthly expenses are $1,850.
Result: Your monthly cash flow is $350 ($2,200 – $1,850).
Annual Cash Flow: $350 × 12 = $4,200.
ROI: ($4,200 / $55,000) = 7.63% Cash on Cash Return.
Use the calculator above to tweak these numbers based on your specific loan terms and local property tax rates to find your next deal.