#mortgage-calculator-wrapper {
font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
max-width: 800px;
margin: 0 auto;
background: #fff;
padding: 20px;
border-radius: 8px;
box-shadow: 0 4px 15px rgba(0,0,0,0.1);
color: #333;
}
.calc-grid {
display: grid;
grid-template-columns: 1fr 1fr;
gap: 20px;
margin-bottom: 25px;
}
.input-group {
display: flex;
flex-direction: column;
}
.input-group label {
font-weight: 600;
margin-bottom: 8px;
font-size: 14px;
color: #555;
}
.input-group input, .input-group select {
padding: 10px;
border: 1px solid #ccc;
border-radius: 4px;
font-size: 16px;
}
.section-title {
grid-column: 1 / -1;
font-size: 18px;
font-weight: bold;
margin-top: 10px;
border-bottom: 2px solid #eee;
padding-bottom: 5px;
color: #2c3e50;
}
.calc-btn {
grid-column: 1 / -1;
background-color: #2ecc71;
color: white;
border: none;
padding: 15px;
font-size: 18px;
font-weight: bold;
border-radius: 5px;
cursor: pointer;
transition: background 0.3s;
text-align: center;
}
.calc-btn:hover {
background-color: #27ae60;
}
#results-area {
background-color: #f8f9fa;
padding: 20px;
border-radius: 5px;
margin-top: 20px;
border-left: 5px solid #2ecc71;
display: none;
}
.result-row {
display: flex;
justify-content: space-between;
margin-bottom: 10px;
font-size: 15px;
}
.result-row.total {
font-size: 20px;
font-weight: bold;
color: #2c3e50;
border-top: 1px solid #ddd;
padding-top: 10px;
margin-top: 10px;
}
.error-msg {
color: #e74c3c;
font-weight: bold;
display: none;
grid-column: 1 / -1;
text-align: center;
}
.seo-content {
margin-top: 40px;
line-height: 1.6;
}
.seo-content h2 {
color: #2c3e50;
margin-top: 30px;
}
.seo-content p {
margin-bottom: 15px;
}
@media (max-width: 600px) {
.calc-grid {
grid-template-columns: 1fr;
}
}
function calculateMortgage() {
// Get references to 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 resultArea = document.getElementById('results-area');
var errorDisplay = document.getElementById('errorDisplay');
// Parse values
var price = parseFloat(homePriceInput.value);
var down = parseFloat(downPaymentInput.value);
var rate = parseFloat(interestRateInput.value);
var years = parseInt(loanTermInput.value);
var tax = parseFloat(propertyTaxInput.value);
var insurance = parseFloat(homeInsuranceInput.value);
var hoa = parseFloat(hoaFeesInput.value);
// Default empty inputs to 0 for optional fields
if (isNaN(down)) down = 0;
if (isNaN(tax)) tax = 0;
if (isNaN(insurance)) insurance = 0;
if (isNaN(hoa)) hoa = 0;
// Validate critical inputs
if (isNaN(price) || isNaN(rate) || price <= 0 || rate < 0) {
errorDisplay.style.display = 'block';
resultArea.style.display = 'none';
return;
}
errorDisplay.style.display = 'none';
// Calculations
var loanAmount = price – down;
// If down payment is greater than price
if (loanAmount < 0) {
loanAmount = 0;
}
var monthlyRate = rate / 100 / 12;
var numberOfPayments = years * 12;
var monthlyPI = 0;
// Mortgage Formula: M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1 ]
if (monthlyRate === 0) {
monthlyPI = loanAmount / numberOfPayments;
} else {
monthlyPI = loanAmount * (monthlyRate * Math.pow(1 + monthlyRate, numberOfPayments)) / (Math.pow(1 + monthlyRate, numberOfPayments) – 1);
}
if (isNaN(monthlyPI) || !isFinite(monthlyPI)) {
monthlyPI = 0;
}
var monthlyTax = tax / 12;
var monthlyInsurance = insurance / 12;
var totalMonthlyPayment = monthlyPI + monthlyTax + monthlyInsurance + hoa;
// formatting currency
var formatter = new Intl.NumberFormat('en-US', {
style: 'currency',
currency: 'USD',
minimumFractionDigits: 2
});
// Update DOM
document.getElementById('res-pi').innerText = formatter.format(monthlyPI);
document.getElementById('res-tax').innerText = formatter.format(monthlyTax);
document.getElementById('res-ins').innerText = formatter.format(monthlyInsurance);
document.getElementById('res-hoa').innerText = formatter.format(hoa);
document.getElementById('res-total').innerText = formatter.format(totalMonthlyPayment);
document.getElementById('res-loan-amount').innerText = formatter.format(loanAmount);
// Show results
resultArea.style.display = 'block';
}
Advanced Mortgage Payment Calculator
Please verify all inputs are positive numbers.
Loan Details
30 Years
20 Years
15 Years
10 Years
Additional Expenses (Annual/Monthly)
Principal & Interest:
$0.00
Property Tax (Monthly):
$0.00
Home Insurance (Monthly):
$0.00
HOA Fees:
$0.00
Total Monthly Payment:
$0.00
Loan Amount: $0
Understanding Your Mortgage Breakdown
Purchasing a home is likely the largest financial commitment you will make in your lifetime. While the listing price is the headline number, the actual affordability of a home depends heavily on your monthly mortgage payment. This calculator provides a comprehensive breakdown of what you can expect to pay every month, going beyond just the loan repayment.
PITI: The Four Pillars of Mortgage Payments
Your total monthly payment is often referred to as PITI, which stands for:
- Principal: The portion of your payment that goes toward paying down the actual money you borrowed. In the early years of a mortgage, this amount is small compared to the interest.
- Interest: The fee you pay to the lender for borrowing the money. Interest rates fluctuate based on economic conditions and your credit score. Even a 0.5% difference can save or cost you tens of thousands of dollars over the life of the loan.
- Taxes: Property taxes are assessed by your local government to fund services like schools and roads. These are usually bundled into your monthly payment and held in escrow by your lender.
- Insurance: Homeowners insurance protects your property against damage. Like taxes, this annual premium is divided by 12 and added to your monthly bill.
How HOA Fees Impact Affordability
If you are buying a condo, townhome, or a house in a planned community, you likely have Homeowners Association (HOA) fees. These are distinct from your mortgage but are mandatory monthly costs that affect your Debt-to-Income (DTI) ratio. Unlike principal and interest, HOA fees do not build equity, so it is crucial to include them in your budget calculations using the field provided above.
30-Year vs. 15-Year Terms
Choosing a loan term is a balancing act. A 30-year mortgage offers lower monthly payments, which can make a more expensive home affordable. However, you will pay significantly more in total interest over the life of the loan. A 15-year mortgage has higher monthly payments but builds equity much faster and offers substantial interest savings.