#mortgage-calculator-container {
font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
max-width: 800px;
margin: 0 auto;
background: #ffffff;
border: 1px solid #e2e8f0;
border-radius: 8px;
box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
overflow: hidden;
}
#mortgage-calculator-container .calc-header {
background: #2563eb;
color: white;
padding: 20px;
text-align: center;
}
#mortgage-calculator-container .calc-header h2 {
margin: 0;
font-size: 24px;
}
#mortgage-calculator-container .calc-body {
padding: 30px;
display: grid;
grid-template-columns: 1fr 1fr;
gap: 30px;
}
@media (max-width: 768px) {
#mortgage-calculator-container .calc-body {
grid-template-columns: 1fr;
}
}
#mortgage-calculator-container .input-group {
margin-bottom: 20px;
}
#mortgage-calculator-container label {
display: block;
margin-bottom: 8px;
font-weight: 600;
color: #374151;
font-size: 14px;
}
#mortgage-calculator-container input,
#mortgage-calculator-container select {
width: 100%;
padding: 10px 12px;
border: 1px solid #d1d5db;
border-radius: 6px;
font-size: 16px;
box-sizing: border-box;
transition: border-color 0.2s;
}
#mortgage-calculator-container input:focus {
outline: none;
border-color: #2563eb;
box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}
#mortgage-calculator-container .calc-btn {
background: #2563eb;
color: white;
border: none;
padding: 12px 24px;
font-size: 16px;
font-weight: 600;
border-radius: 6px;
cursor: pointer;
width: 100%;
transition: background 0.2s;
}
#mortgage-calculator-container .calc-btn:hover {
background: #1d4ed8;
}
#mortgage-calculator-container .results-section {
background: #f8fafc;
padding: 20px;
border-radius: 8px;
border: 1px solid #e2e8f0;
}
#mortgage-calculator-container .result-row {
display: flex;
justify-content: space-between;
margin-bottom: 12px;
padding-bottom: 12px;
border-bottom: 1px solid #e2e8f0;
font-size: 14px;
}
#mortgage-calculator-container .result-row.main-result {
font-size: 18px;
font-weight: 700;
color: #2563eb;
border-bottom: 2px solid #2563eb;
}
#mortgage-calculator-container .result-row:last-child {
border-bottom: none;
margin-bottom: 0;
padding-bottom: 0;
}
#mortgage-calculator-container .seo-content {
padding: 30px;
border-top: 1px solid #e2e8f0;
background: #fff;
color: #374151;
line-height: 1.6;
}
#mortgage-calculator-container .seo-content h3 {
color: #1f2937;
margin-top: 25px;
margin-bottom: 15px;
}
#mortgage-calculator-container .seo-content p {
margin-bottom: 15px;
}
#mortgage-calculator-container .seo-content ul {
padding-left: 20px;
margin-bottom: 15px;
}
#mortgage-calculator-container .seo-content li {
margin-bottom: 8px;
}
.error-msg {
color: #dc2626;
font-size: 13px;
margin-top: 5px;
display: none;
}
function calculateMortgage() {
// Get inputs
var homePrice = parseFloat(document.getElementById('mc-home-price').value);
var downPayment = parseFloat(document.getElementById('mc-down-payment').value);
var interestRate = parseFloat(document.getElementById('mc-interest-rate').value);
var loanTermYears = parseFloat(document.getElementById('mc-loan-term').value);
var annualTax = parseFloat(document.getElementById('mc-property-tax').value);
var annualIns = parseFloat(document.getElementById('mc-home-insurance').value);
// Validation
var errorDiv = document.getElementById('mc-error');
if (isNaN(homePrice) || isNaN(downPayment) || isNaN(interestRate) || isNaN(loanTermYears) ||
homePrice < 0 || downPayment < 0 || interestRate = home price
if (principal 0 && monthlyRate > 0) {
monthlyPI = principal * (monthlyRate * Math.pow(1 + monthlyRate, numberOfPayments)) / (Math.pow(1 + monthlyRate, numberOfPayments) – 1);
} else if (principal > 0 && monthlyRate === 0) {
monthlyPI = principal / numberOfPayments;
}
var monthlyTax = (isNaN(annualTax) ? 0 : annualTax) / 12;
var monthlyIns = (isNaN(annualIns) ? 0 : annualIns) / 12;
var totalMonthly = monthlyPI + monthlyTax + monthlyIns;
var totalCost = (monthlyPI * numberOfPayments);
var totalInterest = totalCost – principal;
if (principal === 0) {
totalInterest = 0;
}
// Calculate Payoff Date
var today = new Date();
var payoffDate = new Date(today.setMonth(today.getMonth() + numberOfPayments));
var dateString = payoffDate.toLocaleDateString('en-US', { month: 'long', year: 'numeric' });
// Format Currency
var formatter = new Intl.NumberFormat('en-US', {
style: 'currency',
currency: 'USD',
minimumFractionDigits: 2
});
// Update UI
document.getElementById('mc-result-monthly').innerText = formatter.format(totalMonthly);
document.getElementById('mc-result-pi').innerText = formatter.format(monthlyPI);
document.getElementById('mc-result-tax').innerText = formatter.format(monthlyTax);
document.getElementById('mc-result-ins').innerText = formatter.format(monthlyIns);
document.getElementById('mc-result-loan-amount').innerText = formatter.format(principal);
document.getElementById('mc-result-total-interest').innerText = formatter.format(totalInterest);
document.getElementById('mc-result-date').innerText = dateString;
}
// Initialize on load with default values
window.onload = function() {
calculateMortgage();
};
Mortgage Payment Calculator
30 Years
20 Years
15 Years
10 Years
Please enter valid positive numbers.
Monthly Payment
$0.00
Principal & Interest
$0.00
Property Tax (Monthly)
$0.00
Home Insurance (Monthly)
$0.00
Total Loan Amount
$0.00
Total Interest Paid
$0.00
Payoff Date
–
How to Calculate Your Mortgage Payment
Understanding your monthly mortgage obligation is the first step in the home buying journey. This calculator breaks down the principal, interest, taxes, and insurance (often called PITI) to give you a realistic estimate of your monthly housing costs.
The Mortgage Formula Explained
Our calculator uses the standard amortization formula to determine your Principal and Interest (P&I) payments:
M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1 ]
Where:
- M = Total monthly payment
- P = Principal loan amount (Home Price minus Down Payment)
- i = Monthly interest rate (Annual Rate divided by 12)
- n = Number of months (Loan Term in years multiplied by 12)
Example Calculation
Let's say you are buying a home for $350,000 with a 20% down payment ($70,000). This leaves you with a loan amount of $280,000.
If you secure a 30-year fixed-rate mortgage at an interest rate of 6.5%:
- Your Principal & Interest payment would be approximately $1,770 per month.
- If annual property taxes are $4,500, that adds $375/mo.
- If annual insurance is $1,200, that adds $100/mo.
- Total Estimated Payment: $2,245 / month.
Factors Affecting Your Mortgage Payment
Down Payment: A larger down payment reduces your principal loan amount, which lowers your monthly payment and total interest paid over the life of the loan. If you put down less than 20%, you may also have to pay Private Mortgage Insurance (PMI).
Interest Rate: Even a small difference in percentage points can significantly impact your monthly payment. Credit score, loan type, and economic conditions all influence the rate lenders offer.
Loan Term: A 15-year term typically has higher monthly payments than a 30-year term, but you will pay significantly less in total interest.