Estimate your monthly mortgage payments including principal, interest, taxes, and insurance (PITI).
30 Years
20 Years
15 Years
10 Years
Estimated Monthly Payment
Principal & Interest:$0.00
Property Taxes:$0.00
Homeowners Insurance:$0.00
HOA Fees:$0.00
Total Monthly Payment:$0.00
Total Loan Amount:$0.00
Total Interest Paid over Loan Life:$0.00
Understanding Your Mortgage Payment
Calculating your mortgage payment is a critical step in the home buying process. This calculator helps you understand the components of your monthly payment, often referred to as PITI (Principal, Interest, Taxes, and Insurance). By accurately estimating these costs, you can determine a home price that fits your budget.
Key Components of a Mortgage Payment
Principal: The portion of your payment that goes toward reducing the loan balance.
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.
Property Taxes: Taxes assessed by your local government, usually held in an escrow account by your lender.
Homeowners Insurance: Protects your home against damage. Lenders require this to protect their investment.
HOA Fees: If you buy a condo or a home in a planned community, you may pay Homeowners Association fees directly to the association.
How Interest Rates Affect Your Buying Power
Even a small change in interest rates can significantly impact your monthly payment and the total interest paid 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.
What is a good Debt-to-Income (DTI) ratio?
Lenders typically look for a DTI ratio of 36% or less, though some loans allow for higher ratios up to 43% or even 50% in certain cases. This ratio compares your total monthly debt payments to your gross monthly income.
Should I pay 20% down?
Putting 20% down helps you avoid Private Mortgage Insurance (PMI), which is an extra cost added to your monthly payment to protect the lender if you default. However, many buyers purchase homes with as little as 3% or 3.5% down depending on the loan type.
function calculateMortgage() {
// Get Input Values
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 propertyTaxAnnual = parseFloat(document.getElementById('propertyTax').value);
var homeInsuranceAnnual = parseFloat(document.getElementById('homeInsurance').value);
var hoaFeesMonthly = parseFloat(document.getElementById('hoaFees').value);
// Validation
if (isNaN(homePrice) || isNaN(downPayment) || isNaN(interestRateAnnual)) {
alert("Please enter valid numbers for Home Price, Down Payment, and Interest Rate.");
return;
}
// Core Calculations
var loanAmount = homePrice – downPayment;
var monthlyInterestRate = (interestRateAnnual / 100) / 12;
var numberOfPayments = loanTermYears * 12;
// Monthly Tax and Insurance
var monthlyTax = propertyTaxAnnual / 12;
var monthlyInsurance = homeInsuranceAnnual / 12;
// Amortization Formula: M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1 ]
var monthlyPrincipalAndInterest = 0;
if (interestRateAnnual === 0) {
monthlyPrincipalAndInterest = loanAmount / numberOfPayments;
} else {
monthlyPrincipalAndInterest = loanAmount * (
(monthlyInterestRate * Math.pow(1 + monthlyInterestRate, numberOfPayments)) /
(Math.pow(1 + monthlyInterestRate, numberOfPayments) – 1)
);
}
var totalMonthlyPayment = monthlyPrincipalAndInterest + monthlyTax + monthlyInsurance + hoaFeesMonthly;
var totalCostOfLoan = (monthlyPrincipalAndInterest * numberOfPayments);
var totalInterestPaid = totalCostOfLoan – loanAmount;
// Formatting Currency
var formatter = new Intl.NumberFormat('en-US', {
style: 'currency',
currency: 'USD',
minimumFractionDigits: 2
});
// Display Results
document.getElementById('res-pi').innerHTML = formatter.format(monthlyPrincipalAndInterest);
document.getElementById('res-tax').innerHTML = formatter.format(monthlyTax);
document.getElementById('res-ins').innerHTML = formatter.format(monthlyInsurance);
document.getElementById('res-hoa').innerHTML = formatter.format(hoaFeesMonthly);
document.getElementById('res-total').innerHTML = formatter.format(totalMonthlyPayment);
document.getElementById('res-loan-amount').innerHTML = formatter.format(loanAmount);
document.getElementById('res-total-interest').innerHTML = formatter.format(totalInterestPaid);
// Show Results Area
document.getElementById('results-area').style.display = 'block';
}