Please enter valid positive numbers for Home Price, Down Payment, and Interest Rate.
Estimated Monthly Payment
$0.00
Principal & Interest$0.00
Property Tax (Monthly)$0.00
Home Insurance (Monthly)$0.00
HOA Fees$0.00
Total Loan Amount$0.00
Total Interest Paid (Over Term)$0.00
Understanding Your Mortgage Payment
Buying a home is one of the largest financial decisions you will make. While the listing price of a home is important, your monthly mortgage payment is often the specific metric that determines affordability. This Mortgage Payment Calculator helps you estimate your monthly costs by breaking them down into four key components: Principal, Interest, Taxes, and Insurance (often referred to as PITI), along with Homeowners Association (HOA) fees.
1. Principal and Interest
The core of your mortgage payment consists of the principal and interest. The principal is the money you borrowed to buy the home, while the interest is what the lender charges you for loaning that money. In the early years of a typical 30-year fixed-rate mortgage, a large portion of your payment goes toward interest. As time passes, more of your payment is applied to the principal balance, building your equity.
2. Property Taxes and Insurance
Most lenders require you to pay a portion of your annual property taxes and homeowners insurance premiums each month. These funds are held in an escrow account and paid on your behalf when they are due.
Property Taxes: Assessed by your local government, usually based on the value of your property.
Homeowners Insurance: Protects your home against damage from fire, theft, and other disasters.
3. HOA Fees
If you are buying a condo, townhouse, or a home in a planned community, you may be required to pay Homeowners Association (HOA) fees. These fees cover common area maintenance, amenities, and sometimes utilities. Unlike taxes and insurance, HOA fees are typically paid directly to the association, but our calculator includes them to give you a complete picture of your monthly housing expenses.
How the Loan Term Affects Your Payment
The term of your loan significantly impacts your monthly payment and the total interest you pay over the life of the loan.
30-Year Term: Offers lower monthly payments because the loan is spread out over a longer period. However, you will pay significantly more in total interest.
15-Year Term: Results in higher monthly payments, but you build equity faster and pay much less in total interest.
Using This Calculator
To get the most accurate estimate, enter the specific details of your potential loan. If you don't know the exact property tax or insurance rates, you can typically estimate property taxes at 1.0% – 1.5% of the home value annually, and insurance at roughly 0.3% – 0.5% of the home value.
function calculateMortgage() {
// 1. Get DOM elements
var homePriceInput = document.getElementById("homePrice");
var downPaymentInput = document.getElementById("downPayment");
var interestRateInput = document.getElementById("interestRate");
var loanTermInput = document.getElementById("loanTerm");
var propertyTaxInput = document.getElementById("propertyTax");
var homeInsuranceInput = document.getElementById("homeInsurance");
var hoaFeesInput = document.getElementById("hoaFees");
var resultBox = document.getElementById("mpResults");
var errorBox = document.getElementById("mpError");
// 2. Parse values
var price = parseFloat(homePriceInput.value);
var down = parseFloat(downPaymentInput.value);
var rate = parseFloat(interestRateInput.value);
var termYears = parseInt(loanTermInput.value);
var taxYearly = parseFloat(propertyTaxInput.value);
var insYearly = parseFloat(homeInsuranceInput.value);
var hoaMonthly = parseFloat(hoaFeesInput.value);
// Handle empty optional fields (set to 0 if NaN or empty)
if (isNaN(taxYearly)) taxYearly = 0;
if (isNaN(insYearly)) insYearly = 0;
if (isNaN(hoaMonthly)) hoaMonthly = 0;
if (isNaN(down)) down = 0;
// 3. Validation
if (isNaN(price) || isNaN(rate) || price <= 0 || rate < 0) {
errorBox.style.display = "block";
resultBox.style.display = "none";
return;
}
errorBox.style.display = "none";
// 4. Calculations
var principal = price – down;
if (principal Price
}
var monthlyRate = rate / 100 / 12;
var totalPayments = termYears * 12;
var monthlyPrincipalInterest = 0;
// Mortgage Formula: M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1]
if (monthlyRate === 0) {
monthlyPrincipalInterest = principal / totalPayments;
} else {
var x = Math.pow(1 + monthlyRate, totalPayments);
monthlyPrincipalInterest = principal * ((monthlyRate * x) / (x – 1));
}
var monthlyTax = taxYearly / 12;
var monthlyIns = insYearly / 12;
var totalMonthlyPayment = monthlyPrincipalInterest + monthlyTax + monthlyIns + hoaMonthly;
var totalInterestPaid = (monthlyPrincipalInterest * totalPayments) – principal;
// Handle cases where principal is 0
if (principal === 0) {
totalInterestPaid = 0;
monthlyPrincipalInterest = 0;
}
// 5. Update DOM with formatted currency
document.getElementById("resTotalMonthly").innerText = formatCurrency(totalMonthlyPayment);
document.getElementById("resPrincipalInterest").innerText = formatCurrency(monthlyPrincipalInterest);
document.getElementById("resPropertyTax").innerText = formatCurrency(monthlyTax);
document.getElementById("resHomeInsurance").innerText = formatCurrency(monthlyIns);
document.getElementById("resHoa").innerText = formatCurrency(hoaMonthly);
document.getElementById("resLoanAmount").innerText = formatCurrency(principal);
document.getElementById("resTotalInterest").innerText = formatCurrency(totalInterestPaid);
// Show results
resultBox.style.display = "block";
}
function formatCurrency(num) {
return "$" + num.toFixed(2).replace(/\d(?=(\d{3})+\.)/g, '$&,');
}