Estimate your monthly mortgage payments including principal, interest, taxes, and insurance (PITI).
30 Years
20 Years
15 Years
10 Years
Please enter valid numeric values for all fields.
Estimated Monthly Payment
$0.00
Payment Breakdown
Principal & Interest:$0.00
Property Tax (Monthly):$0.00
Home Insurance (Monthly):$0.00
HOA Fees (Monthly):$0.00
Loan Summary
Total Loan Amount:$0.00
Total Interest Paid:$0.00
Total Cost of Loan:$0.00
Payoff Date:–
function calculateMortgage() {
// Get inputs
var homePrice = parseFloat(document.getElementById("homePrice").value);
var downPayment = parseFloat(document.getElementById("downPayment").value);
var loanTermYears = parseInt(document.getElementById("loanTerm").value);
var interestRateAnnual = parseFloat(document.getElementById("interestRate").value);
var propertyTaxYearly = parseFloat(document.getElementById("propertyTax").value);
var homeInsuranceYearly = parseFloat(document.getElementById("homeInsurance").value);
var hoaFeesMonthly = parseFloat(document.getElementById("hoaFees").value);
// Validation
if (isNaN(homePrice) || isNaN(downPayment) || isNaN(loanTermYears) || isNaN(interestRateAnnual)) {
document.getElementById("errorMsg").style.display = "block";
document.getElementById("resultsSection").style.display = "none";
return;
}
// Handle optional fields if empty/NaN
if (isNaN(propertyTaxYearly)) propertyTaxYearly = 0;
if (isNaN(homeInsuranceYearly)) homeInsuranceYearly = 0;
if (isNaN(hoaFeesMonthly)) hoaFeesMonthly = 0;
document.getElementById("errorMsg").style.display = "none";
// Calculation Logic
var loanAmount = homePrice – downPayment;
var numPayments = loanTermYears * 12;
var monthlyInterestRate = (interestRateAnnual / 100) / 12;
var monthlyPrincipalInterest = 0;
if (monthlyInterestRate === 0) {
monthlyPrincipalInterest = loanAmount / numPayments;
} else {
monthlyPrincipalInterest = loanAmount *
(monthlyInterestRate * Math.pow(1 + monthlyInterestRate, numPayments)) /
(Math.pow(1 + monthlyInterestRate, numPayments) – 1);
}
// Monthly Taxes and Insurance
var monthlyTax = propertyTaxYearly / 12;
var monthlyInsurance = homeInsuranceYearly / 12;
// Total Monthly Payment (PITI + HOA)
var totalMonthly = monthlyPrincipalInterest + monthlyTax + monthlyInsurance + hoaFeesMonthly;
// Totals over life of loan
var totalPrincipalInterestCost = monthlyPrincipalInterest * numPayments;
var totalInterest = totalPrincipalInterestCost – loanAmount;
var totalLoanCost = totalPrincipalInterestCost + (monthlyTax * numPayments) + (monthlyInsurance * numPayments) + (hoaFeesMonthly * numPayments);
// Payoff Date Estimate
var today = new Date();
var payoffYear = today.getFullYear() + loanTermYears;
var payoffMonth = today.toLocaleString('default', { month: 'long' });
var payoffDateString = payoffMonth + " " + payoffYear;
// Update UI
document.getElementById("totalMonthlyPayment").innerText = formatCurrency(totalMonthly);
document.getElementById("resPrincipalInterest").innerText = formatCurrency(monthlyPrincipalInterest);
document.getElementById("resTax").innerText = formatCurrency(monthlyTax);
document.getElementById("resInsurance").innerText = formatCurrency(monthlyInsurance);
document.getElementById("resHoa").innerText = formatCurrency(hoaFeesMonthly);
document.getElementById("resLoanAmount").innerText = formatCurrency(loanAmount);
document.getElementById("resTotalInterest").innerText = formatCurrency(totalInterest);
document.getElementById("resTotalCost").innerText = formatCurrency(totalPrincipalInterestCost); // Just P&I cost usually standard for "Total Cost of Loan" in finance terms, or use total payments. Let's use Total Cost (P+I) to avoid confusion with sunk costs like taxes.
document.getElementById("resPayoffDate").innerText = payoffDateString;
document.getElementById("resultsSection").style.display = "block";
}
function formatCurrency(num) {
return "$" + num.toFixed(2).replace(/\d(?=(\d{3})+\.)/g, '$&,');
}
Understanding Your Mortgage Payment
Purchasing a home is likely the largest financial commitment you will make in your lifetime. Understanding exactly where your monthly payment goes is crucial for maintaining financial health. This Mortgage Calculator is designed to give you a comprehensive breakdown of your financial obligations, moving beyond just the loan repayment to include the "hidden" costs of homeownership.
What is PITI?
When lenders quote a mortgage payment, they are often referring to just the Principal and Interest. However, your actual monthly check usually covers four distinct parts, collectively known as PITI:
Principal: The portion of your payment that goes toward reducing the loan balance. In the early years of a mortgage, this amount is small.
Interest: The cost of borrowing money. Initially, this makes up the bulk of your payment.
Taxes: Property taxes charged by your local government, usually held in an escrow account by your lender.
Insurance: Homeowners insurance to protect against damage, also typically held in escrow.
How Interest Rates Affect Buying Power
Even a small change in interest rates can drastically alter your monthly payment and the total cost of your home. For example, on a $400,000 loan, a 1% increase in interest rate can increase your monthly payment by hundreds of dollars and your total interest paid over 30 years by nearly $100,000. Use the calculator above to scenario-test different rates to see what you can afford.
The Impact of the Loan Term
Most homebuyers opt for a 30-year fixed-rate mortgage because it offers the lowest monthly payments. However, a 15-year term typically comes with a lower interest rate and allows you to build equity much faster. While the monthly payment is higher, the total interest savings over the life of the loan can be massive.
Don't Forget HOA Fees
If you are buying a condo, townhouse, or a home in a planned community, you will likely have to pay Homeowners Association (HOA) fees. These are rarely included in lender estimates but can significantly impact your debt-to-income ratio. Our calculator allows you to input these fees to get a true "out-the-door" monthly cost.
Frequently Asked Questions
How much down payment do I need?
While 20% is the gold standard to avoid Private Mortgage Insurance (PMI), many buyers qualify for loans with as little as 3% or 3.5% down (FHA loans). Keep in mind that a lower down payment results in a higher loan balance and higher monthly payments.
What is an escrow account?
An escrow account is a savings account managed by your mortgage servicer. A portion of your monthly payment is deposited here to pay your property taxes and insurance premiums when they are due. This ensures you never fall behind on these critical bills.
Should I pay points to lower my rate?
Discount points are upfront fees paid to the lender at closing in exchange for a lower interest rate. If you plan to stay in the home for a long time (7-10+ years), paying points can save you money. Use the calculator to compare the monthly savings against the upfront cost.