Estimate your monthly payments, including taxes, insurance, and HOA fees.
30 Years
20 Years
15 Years
10 Years
Please enter valid positive numbers for all fields.
Principal & Interest:$0.00
Property Taxes (Monthly):$0.00
Home Insurance (Monthly):$0.00
HOA Fees (Monthly):$0.00
TOTAL MONTHLY PAYMENT:$0.00
Total Interest Paid:$0.00
Payoff Date:–
Understanding Your Mortgage Calculation
Calculating your mortgage payment is one of the most critical steps in the home buying process. This Comprehensive Mortgage Calculator goes beyond simple principal and interest calculations to give you a realistic view of your monthly financial commitment. By factoring in property taxes, homeowner's insurance, and HOA fees, you avoid the "payment shock" that many first-time homebuyers experience.
The Four Pillars of a Mortgage Payment (PITI)
Mortgage lenders often refer to your monthly payment as PITI. Understanding these components helps you budget effectively:
Principal: This is the portion of your payment that goes directly toward paying down the loan balance. In the early years of a 30-year mortgage, this amount is small but grows over time.
Interest: This is the cost of borrowing money. Initially, interest makes up the majority of your payment. Our calculator uses the standard amortization formula to determine this split.
Taxes: Property taxes are assessed by your local government to fund schools and public services. Lenders typically collect 1/12th of your annual tax bill each month and hold it in an escrow account.
Insurance: Homeowner's insurance protects your property against damage. Like taxes, this is usually paid monthly into an escrow account.
How Interest Rates Impact Your Buying Power
Even a small change in interest rates can significantly affect your monthly payment and total loan cost. For example, on a $300,000 loan, a 1% increase in interest rate can raise your monthly payment by over $180 and cost you an additional $65,000+ in interest over the life of a 30-year loan. Use the "Interest Rate" field in the calculator above to see how different rates impact your bottom line.
The Impact of Loan Term
Choosing between a 15-year and a 30-year mortgage is a common dilemma. A 30-year term offers lower monthly payments, making homes more affordable month-to-month. However, a 15-year term typically comes with a lower interest rate and significantly reduces the total interest paid, though the monthly payment is higher. Toggle the "Loan Term" dropdown to compare these scenarios instantly.
Don't Forget HOA Fees
If you are buying a condo, townhome, or a house in a planned community, you will likely pay Homeowners Association (HOA) fees. These are paid directly to the association to cover common area maintenance and amenities. While not part of the loan, lenders count this debt against your qualifying ratios. Our calculator includes a dedicated field for HOA fees to ensure your total monthly estimate is accurate.
How to Use This Calculator
Enter Home Price: The total purchase price of the property.
Input Down Payment: The cash amount you are paying upfront. The calculator automatically subtracts this from the home price to find your loan amount.
Set Rate & Term: Enter the current interest rate and choose your loan duration.
Add Escrow Details: Input annual estimates for Property Tax and Insurance. You can usually find tax history on real estate listing sites.
Review Results: Click "Calculate Payments" to see a detailed breakdown of where your money goes every month.
// Set default date to today
var today = new Date();
var dd = String(today.getDate()).padStart(2, '0');
var mm = String(today.getMonth() + 1).padStart(2, '0');
var yyyy = today.getFullYear();
document.getElementById('startDate').value = yyyy + '-' + mm + '-' + dd;
function calculateMortgage() {
// 1. Get Input Values
var homePrice = parseFloat(document.getElementById('homePrice').value);
var downPayment = parseFloat(document.getElementById('downPayment').value);
var interestRate = parseFloat(document.getElementById('interestRate').value);
var loanTermYears = parseInt(document.getElementById('loanTerm').value);
var annualTax = parseFloat(document.getElementById('propertyTax').value);
var annualInsurance = parseFloat(document.getElementById('homeInsurance').value);
var monthlyHOA = parseFloat(document.getElementById('hoaFees').value);
var startDateInput = document.getElementById('startDate').value;
// 2. Validate Inputs
if (isNaN(homePrice) || isNaN(downPayment) || isNaN(interestRate) ||
isNaN(loanTermYears) || isNaN(annualTax) || isNaN(annualInsurance) ||
isNaN(monthlyHOA) || homePrice < 0 || downPayment < 0) {
document.getElementById('errorMsg').style.display = 'block';
document.getElementById('resultSection').style.display = 'none';
return;
}
document.getElementById('errorMsg').style.display = 'none';
// 3. Perform Calculations
var principal = homePrice – downPayment;
var monthlyRate = (interestRate / 100) / 12;
var numberOfPayments = loanTermYears * 12;
// Calculate P&I
var monthlyPrincipalAndInterest = 0;
if (interestRate === 0) {
monthlyPrincipalAndInterest = principal / numberOfPayments;
} else {
// M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1 ]
monthlyPrincipalAndInterest = principal *
(monthlyRate * Math.pow(1 + monthlyRate, numberOfPayments)) /
(Math.pow(1 + monthlyRate, numberOfPayments) – 1);
}
// Calculate other monthly costs
var monthlyTax = annualTax / 12;
var monthlyInsurance = annualInsurance / 12;
var totalMonthlyPayment = monthlyPrincipalAndInterest + monthlyTax + monthlyInsurance + monthlyHOA;
var totalLoanCost = (monthlyPrincipalAndInterest * numberOfPayments);
var totalInterest = totalLoanCost – principal;
// Calculate Payoff Date
var start = new Date(startDateInput);
if (isNaN(start.getTime())) { start = new Date(); } // fallback to today if empty
start.setMonth(start.getMonth() + numberOfPayments);
var payoffMonth = start.toLocaleString('default', { month: 'long' });
var payoffYear = start.getFullYear();
// 4. Format and Display Results
var formatter = new Intl.NumberFormat('en-US', {
style: 'currency',
currency: 'USD',
minimumFractionDigits: 2
});
document.getElementById('piResult').innerText = formatter.format(monthlyPrincipalAndInterest);
document.getElementById('taxResult').innerText = formatter.format(monthlyTax);
document.getElementById('insResult').innerText = formatter.format(monthlyInsurance);
document.getElementById('hoaResult').innerText = formatter.format(monthlyHOA);
document.getElementById('totalMonthlyResult').innerText = formatter.format(totalMonthlyPayment);
document.getElementById('totalInterestResult').innerText = formatter.format(totalInterest);
document.getElementById('payoffDateResult').innerText = payoffMonth + " " + payoffYear;
document.getElementById('resultSection').style.display = 'block';
}