Rental Property Cash Flow Calculator
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Total Monthly Income:
$0.00
Total Monthly Expenses:
$0.00
Net Operating Income (NOI):
$0.00
Monthly Cash Flow:
$0.00
Yearly Cash Flow: $0.00
Understanding Rental Property Cash Flow
Cash flow is the lifeblood of any real estate investment. It represents the net amount of money moving in or out of your business after all expenses have been paid. For rental property investors, calculating accurate cash flow is critical to determining whether a property is a liability or an asset.
Many novice investors make the mistake of calculating cash flow simply as Rent – Mortgage. This is a dangerous oversimplification that often leads to negative returns. A true cash flow analysis must account for vacancy, repairs, capital expenditures (CapEx), and management fees.
How to Use This Calculator
This tool is designed to provide a comprehensive view of your investment's performance:
- Gross Income: Enter your total expected rent plus any ancillary income (laundry, parking, storage fees).
- Fixed Expenses: These are bills you must pay every month regardless of occupancy, such as mortgage principal/interest, taxes, insurance, and HOA fees.
- Variable Expenses: These are percentage-based estimates. Even if you don't spend money on repairs this month, you should budget for them. We recommend allocating 5-10% each for Vacancy, Repairs, and CapEx.
What is a Good Cash Flow?
While "good" is subjective based on your market and strategy, many investors aim for:
- $100 – $200 per door: Minimum standard for many buy-and-hold investors.
- $300+ per door: considered a strong performing asset.
- Cash-on-Cash Return: Often a better metric than raw dollars, aiming for 8-12% or higher.
Key Metrics Defined
Net Operating Income (NOI): This is your total income minus all operating expenses, excluding the mortgage payment. It measures the profitability of the property itself, independent of financing.
Capital Expenditures (CapEx): These are major expenses that occur infrequently, such as replacing a roof, HVAC system, or water heater. Allocating a percentage of rent monthly ensures you have the funds when these big-ticket items inevitably break.
function calculateRentalCashFlow() {
// 1. Get Income Inputs
var rent = parseFloat(document.getElementById('rentAmount').value) || 0;
var otherIncome = parseFloat(document.getElementById('otherIncome').value) || 0;
// 2. Get Fixed Expense Inputs
var mortgage = parseFloat(document.getElementById('mortgagePayment').value) || 0;
var tax = parseFloat(document.getElementById('propertyTax').value) || 0;
var insurance = parseFloat(document.getElementById('insuranceCost').value) || 0;
var hoa = parseFloat(document.getElementById('hoaFee').value) || 0;
// 3. Get Variable Rate Inputs (Percentage)
var vacancyPct = parseFloat(document.getElementById('vacancyRate').value) || 0;
var repairsPct = parseFloat(document.getElementById('repairsRate').value) || 0;
var capexPct = parseFloat(document.getElementById('capexRate').value) || 0;
var managementPct = parseFloat(document.getElementById('managementFee').value) || 0;
// 4. Calculate Totals
var totalIncome = rent + otherIncome;
// Calculate variable dollar amounts
var vacancyCost = totalIncome * (vacancyPct / 100);
var repairsCost = totalIncome * (repairsPct / 100);
var capexCost = totalIncome * (capexPct / 100);
var managementCost = totalIncome * (managementPct / 100);
// Total Expenses
var totalExpenses = mortgage + tax + insurance + hoa + vacancyCost + repairsCost + capexCost + managementCost;
// Net Operating Income (Income – Operating Expenses, usually excluding financing,
// but for simple cash flow calc we often group them.
// Strictly speaking NOI = Income – (Expenses – Mortgage).
// Here we will display Total Expenses inclusive of mortgage for the final cash flow figure.
var operatingExpensesOnly = tax + insurance + hoa + vacancyCost + repairsCost + capexCost + managementCost;
var noi = totalIncome – operatingExpensesOnly;
var monthlyCashFlow = totalIncome – totalExpenses;
var yearlyCashFlow = monthlyCashFlow * 12;
// 5. Display Results
var resultDiv = document.getElementById('results');
resultDiv.style.display = "block";
document.getElementById('dispTotalIncome').innerText = "$" + totalIncome.toFixed(2).replace(/\d(?=(\d{3})+\.)/g, '$&,');
document.getElementById('dispTotalExpenses').innerText = "$" + totalExpenses.toFixed(2).replace(/\d(?=(\d{3})+\.)/g, '$&,');
document.getElementById('dispNOI').innerText = "$" + noi.toFixed(2).replace(/\d(?=(\d{3})+\.)/g, '$&,');
var cfElement = document.getElementById('dispCashFlow');
cfElement.innerText = "$" + monthlyCashFlow.toFixed(2).replace(/\d(?=(\d{3})+\.)/g, '$&,');
document.getElementById('yearlyCashFlow').innerText = "Yearly Cash Flow: $" + yearlyCashFlow.toFixed(2).replace(/\d(?=(\d{3})+\.)/g, '$&,');
// Styling for positive/negative cash flow
if (monthlyCashFlow >= 0) {
cfElement.className = "positive-cf";
} else {
cfElement.className = "negative-cf";
}
}