.mc-container {
background-color: #f9f9f9;
border: 1px solid #e0e0e0;
border-radius: 8px;
padding: 30px;
margin-bottom: 40px;
box-shadow: 0 4px 6px rgba(0,0,0,0.05);
}
.mc-header {
text-align: center;
margin-bottom: 25px;
color: #2c3e50;
}
.mc-grid {
display: grid;
grid-template-columns: 1fr 1fr;
gap: 20px;
}
.mc-input-group {
display: flex;
flex-direction: column;
}
.mc-label {
font-size: 14px;
font-weight: 600;
margin-bottom: 8px;
color: #555;
}
.mc-input {
padding: 12px;
border: 1px solid #ccc;
border-radius: 4px;
font-size: 16px;
transition: border-color 0.3s;
}
.mc-input:focus {
border-color: #3498db;
outline: none;
}
.mc-btn-container {
grid-column: 1 / -1;
margin-top: 10px;
}
.mc-btn {
width: 100%;
padding: 15px;
background-color: #27ae60;
color: white;
border: none;
border-radius: 4px;
font-size: 18px;
font-weight: bold;
cursor: pointer;
transition: background-color 0.2s;
}
.mc-btn:hover {
background-color: #219150;
}
.mc-results {
grid-column: 1 / -1;
background-color: #fff;
border: 1px solid #eee;
border-radius: 4px;
padding: 20px;
margin-top: 20px;
display: none;
}
.mc-result-row {
display: flex;
justify-content: space-between;
margin-bottom: 10px;
font-size: 15px;
}
.mc-total {
font-size: 24px;
font-weight: 800;
color: #2980b9;
border-top: 2px solid #eee;
padding-top: 15px;
margin-top: 10px;
}
.mc-error {
color: #c0392b;
text-align: center;
margin-top: 10px;
display: none;
}
/* Responsive */
@media (max-width: 600px) {
.mc-grid {
grid-template-columns: 1fr;
}
}
function calculateMortgage() {
// Get Input Values
var price = document.getElementById('mc_home_price').value;
var down = document.getElementById('mc_down_payment').value;
var rate = document.getElementById('mc_interest_rate').value;
var term = document.getElementById('mc_loan_term').value;
var tax = document.getElementById('mc_property_tax').value;
var ins = document.getElementById('mc_insurance').value;
var errorDiv = document.getElementById('mc_error');
var resultsDiv = document.getElementById('mc_results');
// Reset Error
errorDiv.style.display = 'none';
resultsDiv.style.display = 'none';
// Validate Inputs
if (price === "" || down === "" || rate === "" || term === "" || tax === "" || ins === "") {
errorDiv.innerText = "Please fill in all fields.";
errorDiv.style.display = 'block';
return;
}
// Parse Floats
var priceVal = parseFloat(price);
var downVal = parseFloat(down);
var rateVal = parseFloat(rate);
var termVal = parseFloat(term);
var taxVal = parseFloat(tax);
var insVal = parseFloat(ins);
if (isNaN(priceVal) || isNaN(downVal) || isNaN(rateVal) || isNaN(termVal) || isNaN(taxVal) || isNaN(insVal)) {
errorDiv.innerText = "Please enter valid numbers.";
errorDiv.style.display = 'block';
return;
}
// Calculation Logic
var principal = priceVal – downVal;
// Handle edge case where principal is 0 or less
if (principal <= 0) {
errorDiv.innerText = "Down payment cannot equal or exceed home price.";
errorDiv.style.display = 'block';
return;
}
// Monthly Interest Rate
var monthlyRate = (rateVal / 100) / 12;
// Total Number of Payments
var totalPayments = termVal * 12;
// Calculate Monthly Principal & Interest (P&I)
// Formula: M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1 ]
var monthlyPI = 0;
if (rateVal === 0) {
monthlyPI = principal / totalPayments;
} else {
var x = Math.pow(1 + monthlyRate, totalPayments);
monthlyPI = (principal * x * monthlyRate) / (x – 1);
}
// Calculate Escrow Items (Tax & Insurance)
var monthlyTax = taxVal / 12;
var monthlyIns = insVal / 12;
// Total Monthly Payment
var totalMonthly = monthlyPI + monthlyTax + monthlyIns;
// Display Results
document.getElementById('mc_res_pi').innerText = "$" + monthlyPI.toFixed(2).replace(/\d(?=(\d{3})+\.)/g, '$&,');
document.getElementById('mc_res_tax').innerText = "$" + monthlyTax.toFixed(2).replace(/\d(?=(\d{3})+\.)/g, '$&,');
document.getElementById('mc_res_ins').innerText = "$" + monthlyIns.toFixed(2).replace(/\d(?=(\d{3})+\.)/g, '$&,');
document.getElementById('mc_res_total').innerText = "$" + totalMonthly.toFixed(2).replace(/\d(?=(\d{3})+\.)/g, '$&,');
resultsDiv.style.display = 'block';
}
Mortgage Payment Calculator
Please fill in all fields with valid numbers.
Principal & Interest:
$0.00
Property Tax (Monthly):
$0.00
Home Insurance (Monthly):
$0.00
Total Monthly Payment:
$0.00
Understanding Your Monthly Mortgage Payment
Purchasing a home is one of the most significant financial decisions you will make in your lifetime. While the listing price of a home gives you a general idea of the cost, your actual monthly obligation involves several components that go beyond just repaying the loan balance. Our Mortgage Payment Calculator is designed to provide a comprehensive breakdown of these costs, helping you determine exactly how much house you can afford.
Components of a Mortgage Payment (PITI)
Lenders often refer to your monthly payment as PITI, which stands for Principal, Interest, Taxes, and Insurance. Understanding these elements is crucial for accurate budgeting:
- Principal: This is the portion of your payment that goes directly toward reducing the loan balance. In the early years of a long-term mortgage, this amount is small but grows over time.
- Interest: This is the cost of borrowing money. With a fixed-rate mortgage, your interest rate remains the same, but the amount of interest you pay decreases as your principal balance goes down.
- Taxes: Property taxes are assessed by your local government to fund services like schools and roads. These are usually divided by 12 and collected monthly by your lender into an escrow account.
- Insurance: Lenders require homeowners insurance to protect the property against damage. Like taxes, the annual premium is typically divided into monthly installments.
How Interest Rates Impact Affordability
Even a small fluctuation in interest rates can dramatically affect your monthly payment and the total cost of the loan. For example, on a $300,000 loan, a difference of just 1% in the interest rate can change your monthly payment by hundreds of dollars and your total interest paid over 30 years by tens of thousands.
The Role of the Down Payment
Your down payment reduces the principal amount you need to borrow. A larger down payment (typically 20% or more) not only lowers your monthly principal and interest payment but also helps you avoid Private Mortgage Insurance (PMI), an extra cost lenders charge borrowers with smaller down payments.