Estimate your monthly house payments with taxes and insurance.
30 Years
20 Years
15 Years
10 Years
Estimated Monthly Payment
Principal & Interest:$0.00
Property Tax:$0.00
Home Insurance:$0.00
HOA Fees:$0.00
TOTAL MONTHLY PAYMENT:$0.00
Loan Summary:
Loan Amount: $0.00
Total Interest Paid (over term): $0.00
Total Cost of Loan: $0.00
How to Calculate Your Mortgage Payments
Understanding exactly how much you will pay for your home each month is crucial for financial planning. This Mortgage Payment Calculator helps you break down the costs associated with buying a home, going beyond just the sticker price to include interest, taxes, insurance, and HOA fees.
Components of Your Monthly Mortgage Payment
Your monthly housing payment typically consists of four main parts, often referred to as PITI:
Principal: The portion of your payment that goes toward paying down the loan balance (the amount you borrowed).
Interest: The cost of borrowing money, paid to the lender. In the early years of a mortgage, a larger portion of your payment goes toward interest.
Taxes: Property taxes assessed by your local government. Lenders often collect this monthly and hold it in an escrow account to pay the bill when it's due.
Insurance: Homeowners insurance protects your property against damage. Like taxes, this is often paid through an escrow account.
How Interest Rates Affect Affordability
Even a small difference in interest rates can have a significant impact on your monthly payment and the total amount you pay over the life of the loan. For example, on a $300,000 loan, a 1% increase in interest rate can increase your monthly payment by hundreds of dollars and your total interest paid by tens of thousands.
Tips for Lowering Your Mortgage Payment
If the calculated payment is higher than your budget allows, consider these strategies:
Increase your down payment: This lowers the principal loan amount and reduces your monthly obligation.
Improve your credit score: A higher credit score often qualifies you for lower interest rates.
Shop around: Different lenders offer different rates and fees. Comparing offers can save you money.
Consider a longer term: A 30-year term will have lower monthly payments than a 15-year term, though you will pay more interest in the long run.
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 propertyTaxYear = parseFloat(document.getElementById('propertyTax').value);
var homeInsuranceYear = parseFloat(document.getElementById('homeInsurance').value);
var hoaFeesMonth = parseFloat(document.getElementById('hoaFees').value);
// 2. Validation
if (isNaN(homePrice) || homePrice <= 0) {
alert("Please enter a valid Home Price.");
return;
}
if (isNaN(downPayment) || downPayment < 0) {
downPayment = 0;
}
if (isNaN(interestRate) || interestRate < 0) {
alert("Please enter a valid Interest Rate.");
return;
}
if (isNaN(propertyTaxYear)) propertyTaxYear = 0;
if (isNaN(homeInsuranceYear)) homeInsuranceYear = 0;
if (isNaN(hoaFeesMonth)) hoaFeesMonth = 0;
// 3. Calculation Logic
var loanAmount = homePrice – downPayment;
// If down payment is greater than home price
if (loanAmount < 0) {
alert("Down payment cannot be greater than Home Price.");
return;
}
var monthlyInterestRate = (interestRate / 100) / 12;
var totalPayments = loanTermYears * 12;
var monthlyPrincipalInterest = 0;
// Handle 0% interest case
if (interestRate === 0) {
monthlyPrincipalInterest = loanAmount / totalPayments;
} else {
// Standard Amortization Formula: M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1 ]
monthlyPrincipalInterest = loanAmount *
(monthlyInterestRate * Math.pow(1 + monthlyInterestRate, totalPayments)) /
(Math.pow(1 + monthlyInterestRate, totalPayments) – 1);
}
var monthlyTax = propertyTaxYear / 12;
var monthlyInsurance = homeInsuranceYear / 12;
var totalMonthlyPayment = monthlyPrincipalInterest + monthlyTax + monthlyInsurance + hoaFeesMonth;
var totalInterestPaid = (monthlyPrincipalInterest * totalPayments) – loanAmount;
var totalCostOfLoan = (monthlyPrincipalInterest * totalPayments) + downPayment; // Total cost including down payment? Usually total cost of LOAN is P+I. Let's do Total Paid for House.
// Actually standard metric is "Total Amount Paid" (Principal + Interest)
var totalAmountPaidToLender = monthlyPrincipalInterest * totalPayments;
// 4. Update UI
// Helper for currency formatting
var formatter = new Intl.NumberFormat('en-US', {
style: 'currency',
currency: 'USD',
minimumFractionDigits: 2
});
document.getElementById('resPI').innerText = formatter.format(monthlyPrincipalInterest);
document.getElementById('resTax').innerText = formatter.format(monthlyTax);
document.getElementById('resIns').innerText = formatter.format(monthlyInsurance);
document.getElementById('resHOA').innerText = formatter.format(hoaFeesMonth);
document.getElementById('resTotal').innerText = formatter.format(totalMonthlyPayment);
document.getElementById('resLoanAmount').innerText = formatter.format(loanAmount);
document.getElementById('resTotalInterest').innerText = formatter.format(totalInterestPaid);
document.getElementById('resTotalCost').innerText = formatter.format(totalAmountPaidToLender);
// Show results
document.getElementById('results-area').style.display = 'block';
// Smooth scroll to results
document.getElementById('results-area').scrollIntoView({ behavior: 'smooth' });
}