#mortgage-calculator-container {
font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
max-width: 800px;
margin: 0 auto;
background: #ffffff;
color: #333;
}
.mc-header {
text-align: center;
margin-bottom: 30px;
}
.mc-header h2 {
font-size: 28px;
color: #2c3e50;
margin-bottom: 10px;
}
.mc-grid {
display: grid;
grid-template-columns: 1fr 1fr;
gap: 20px;
background: #f8f9fa;
padding: 25px;
border-radius: 8px;
box-shadow: 0 2px 5px rgba(0,0,0,0.05);
}
.mc-input-group {
margin-bottom: 15px;
}
.mc-input-group label {
display: block;
margin-bottom: 5px;
font-weight: 600;
font-size: 14px;
}
.mc-input-group input, .mc-input-group select {
width: 100%;
padding: 10px;
border: 1px solid #ddd;
border-radius: 4px;
font-size: 16px;
box-sizing: border-box;
}
.mc-input-group input:focus {
border-color: #3498db;
outline: none;
}
.mc-full-width {
grid-column: 1 / -1;
}
.mc-btn {
background-color: #2980b9;
color: white;
border: none;
padding: 15px 30px;
font-size: 18px;
font-weight: bold;
border-radius: 5px;
cursor: pointer;
width: 100%;
transition: background 0.3s;
margin-top: 10px;
}
.mc-btn:hover {
background-color: #2471a3;
}
#mc-results {
margin-top: 30px;
padding: 20px;
background: #e8f6f3;
border: 1px solid #d4efdf;
border-radius: 8px;
display: none;
}
.mc-result-row {
display: flex;
justify-content: space-between;
align-items: center;
padding: 10px 0;
border-bottom: 1px solid #d4efdf;
}
.mc-result-row:last-child {
border-bottom: none;
}
.mc-result-label {
font-size: 16px;
color: #555;
}
.mc-result-value {
font-size: 18px;
font-weight: bold;
color: #2c3e50;
}
.mc-main-result {
text-align: center;
padding: 15px;
background: #fff;
border-radius: 5px;
margin-bottom: 20px;
}
.mc-main-result .val {
font-size: 36px;
color: #27ae60;
display: block;
font-weight: 800;
}
.mc-article {
margin-top: 50px;
line-height: 1.6;
}
.mc-article h3 {
color: #2c3e50;
border-bottom: 2px solid #eee;
padding-bottom: 10px;
margin-top: 30px;
}
.mc-article p {
margin-bottom: 15px;
}
.mc-article ul {
margin-bottom: 15px;
padding-left: 20px;
}
@media (max-width: 600px) {
.mc-grid {
grid-template-columns: 1fr;
}
}
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 = parseInt(document.getElementById('mc-loan-term').value);
var propertyTaxYear = parseFloat(document.getElementById('mc-property-tax').value);
var insuranceYear = parseFloat(document.getElementById('mc-insurance').value);
var hoaMonth = parseFloat(document.getElementById('mc-hoa').value);
// Validation
if (isNaN(homePrice) || isNaN(downPayment) || isNaN(interestRate) || isNaN(loanTermYears)) {
alert("Please enter valid numbers for the main loan details.");
return;
}
// Handle optional fields as 0 if empty
if (isNaN(propertyTaxYear)) propertyTaxYear = 0;
if (isNaN(insuranceYear)) insuranceYear = 0;
if (isNaN(hoaMonth)) hoaMonth = 0;
// Calculations
var principal = homePrice – downPayment;
// If down payment is greater than home price
if (principal < 0) {
alert("Down payment cannot be larger than home price.");
return;
}
var monthlyInterestRate = (interestRate / 100) / 12;
var numberOfPayments = loanTermYears * 12;
// Monthly Principal & Interest Calculation
// Formula: M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1 ]
var monthlyPI = 0;
if (interestRate === 0) {
monthlyPI = principal / numberOfPayments;
} else {
var x = Math.pow(1 + monthlyInterestRate, numberOfPayments);
monthlyPI = (principal * x * monthlyInterestRate) / (x – 1);
}
// Monthly Taxes and Insurance
var monthlyTax = propertyTaxYear / 12;
var monthlyInsurance = insuranceYear / 12;
var totalMonthlyPayment = monthlyPI + monthlyTax + monthlyInsurance + hoaMonth;
var totalCostOfLoan = (monthlyPI * numberOfPayments);
var totalInterest = totalCostOfLoan – principal;
// Update UI
document.getElementById('mc-total-monthly').innerText = formatCurrency(totalMonthlyPayment);
document.getElementById('mc-pi-result').innerText = formatCurrency(monthlyPI);
document.getElementById('mc-tax-result').innerText = formatCurrency(monthlyTax);
document.getElementById('mc-ins-result').innerText = formatCurrency(monthlyInsurance);
document.getElementById('mc-hoa-result').innerText = formatCurrency(hoaMonth);
document.getElementById('mc-loan-amount').innerText = formatCurrency(principal);
document.getElementById('mc-total-interest').innerText = formatCurrency(totalInterest);
// Show results section
document.getElementById('mc-results').style.display = 'block';
}
function formatCurrency(num) {
return '$' + num.toFixed(2).replace(/\d(?=(\d{3})+\.)/g, '$&,');
}
Mortgage Payment Calculator
Estimate your monthly mortgage payments, including interest, taxes, and insurance.
30 Years
20 Years
15 Years
10 Years
Estimated Monthly Payment
$0.00
Principal & Interest
$0.00
Property Tax (Monthly)
$0.00
Home Insurance (Monthly)
$0.00
HOA Fees
$0.00
Total Loan Amount
$0.00
Total Interest Paid
$0.00
How a Mortgage Calculator Works
Using a mortgage calculator is an essential step in the home buying process. It helps prospective homeowners understand their financial obligations before committing to a loan. This tool breaks down the complex amortization formula into simple, readable monthly figures, ensuring you know exactly where your money goes every month.
Understanding Your Monthly Payment
A mortgage payment isn't just about paying back what you borrowed. It is typically comprised of four distinct parts, often referred to by the acronym PITI:
- Principal: The portion of your payment that reduces the remaining balance of your loan. In the early years of a mortgage, this amount is small but grows over time.
- Interest: The fee charged by the lender for the privilege of borrowing money. On a typical 30-year fixed loan, interest makes up the majority of your payment for the first several years.
- 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 covers damages to your property. Like taxes, this is often bundled into your monthly mortgage payment via escrow.
How Interest Rates Affect Your Loan
Even a small difference in interest rates can have a massive impact on your monthly payment and total loan cost. For example, on a $300,000 loan, the difference between a 6.0% rate and a 7.0% rate is approximately $200 per month. Over the life of a 30-year loan, that 1% difference costs you an extra $72,000 in interest.
Strategies to Lower Your Monthly Payment
If the calculated payment is higher than your budget allows, consider these strategies:
- Increase your down payment: Paying more upfront reduces the principal loan amount and may eliminate the need for Private Mortgage Insurance (PMI).
- Extend the loan term: Switching from a 15-year to a 30-year term lowers monthly payments, though you will pay more interest over the long run.
- Shop for lower rates: Improving your credit score or shopping around with different lenders can help you secure a lower interest rate.
Common Questions About Mortgages
What is Private Mortgage Insurance (PMI)?
If your down payment is less than 20% of the home's value, lenders often require PMI to protect them in case of default. This is an extra monthly fee added to your payment.
How much house can I afford?
A general rule of thumb is that your monthly mortgage payment should not exceed 28% of your gross monthly income. This ensures you have enough funds remaining for other debts, savings, and living expenses.