#mortgage-calc-wrapper .calc-box {
background-color: #f9f9f9;
border: 1px solid #e0e0e0;
border-radius: 8px;
padding: 30px;
box-shadow: 0 4px 6px rgba(0,0,0,0.05);
margin-bottom: 40px;
}
#mortgage-calc-wrapper h2 {
color: #2c3e50;
text-align: center;
margin-bottom: 25px;
}
#mortgage-calc-wrapper .form-group {
margin-bottom: 15px;
display: flex;
flex-direction: column;
}
#mortgage-calc-wrapper label {
font-weight: 600;
margin-bottom: 5px;
color: #34495e;
}
#mortgage-calc-wrapper input[type="number"] {
padding: 10px;
border: 1px solid #bdc3c7;
border-radius: 4px;
font-size: 16px;
}
#mortgage-calc-wrapper .row {
display: flex;
gap: 20px;
flex-wrap: wrap;
}
#mortgage-calc-wrapper .col {
flex: 1;
min-width: 200px;
}
#mortgage-calc-wrapper button.calc-btn {
background-color: #27ae60;
color: white;
border: none;
padding: 15px 30px;
font-size: 18px;
font-weight: bold;
border-radius: 5px;
cursor: pointer;
width: 100%;
margin-top: 10px;
transition: background-color 0.3s;
}
#mortgage-calc-wrapper button.calc-btn:hover {
background-color: #219150;
}
#mortgage-calc-wrapper .results-section {
margin-top: 30px;
padding-top: 20px;
border-top: 2px solid #ecf0f1;
display: none;
}
#mortgage-calc-wrapper .result-card {
background: #fff;
padding: 20px;
border-radius: 5px;
border: 1px solid #ddd;
text-align: center;
}
#mortgage-calc-wrapper .big-number {
font-size: 32px;
color: #2c3e50;
font-weight: 800;
margin: 10px 0;
}
#mortgage-calc-wrapper .breakdown-table {
width: 100%;
border-collapse: collapse;
margin-top: 20px;
}
#mortgage-calc-wrapper .breakdown-table th,
#mortgage-calc-wrapper .breakdown-table td {
text-align: left;
padding: 10px;
border-bottom: 1px solid #eee;
}
#mortgage-calc-wrapper .breakdown-table th {
color: #7f8c8d;
font-weight: 600;
}
#mortgage-calc-wrapper .article-section {
line-height: 1.6;
color: #444;
}
#mortgage-calc-wrapper .article-section h3 {
color: #2c3e50;
margin-top: 25px;
}
#mortgage-calc-wrapper .error-msg {
color: #e74c3c;
text-align: center;
font-weight: bold;
margin-top: 10px;
display: none;
}
function calculateMortgage() {
// Get Input Values
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 annualInsurance = parseFloat(document.getElementById('mc_insurance').value);
var monthlyHOA = parseFloat(document.getElementById('mc_hoa').value);
// Validation
if (isNaN(homePrice) || isNaN(downPayment) || isNaN(interestRate) || isNaN(loanTermYears) ||
homePrice < 0 || downPayment < 0 || interestRate < 0 || loanTermYears <= 0) {
document.getElementById('mc_error').style.display = 'block';
document.getElementById('mc_results').style.display = 'none';
return;
} else {
document.getElementById('mc_error').style.display = 'none';
}
// Defaults for optional fields if empty
if (isNaN(annualTax)) annualTax = 0;
if (isNaN(annualInsurance)) annualInsurance = 0;
if (isNaN(monthlyHOA)) monthlyHOA = 0;
// Core Calculations
var loanAmount = homePrice – downPayment;
var monthlyInterestRate = interestRate / 100 / 12;
var numberOfPayments = loanTermYears * 12;
// Principal & Interest Calculation
var monthlyPrincipalAndInterest = 0;
if (interestRate === 0) {
monthlyPrincipalAndInterest = loanAmount / numberOfPayments;
} else {
monthlyPrincipalAndInterest = loanAmount *
(monthlyInterestRate * Math.pow(1 + monthlyInterestRate, numberOfPayments)) /
(Math.pow(1 + monthlyInterestRate, numberOfPayments) – 1);
}
// Other Monthly Costs
var monthlyTax = annualTax / 12;
var monthlyInsurance = annualInsurance / 12;
var totalMonthlyPayment = monthlyPrincipalAndInterest + monthlyTax + monthlyInsurance + monthlyHOA;
// Total Loan Cost
var totalPaymentOverLife = (monthlyPrincipalAndInterest * numberOfPayments);
var totalInterest = totalPaymentOverLife – loanAmount;
// Formatting Function
var formatter = new Intl.NumberFormat('en-US', {
style: 'currency',
currency: 'USD',
minimumFractionDigits: 2
});
// Update DOM
document.getElementById('mc_total_monthly').innerHTML = formatter.format(totalMonthlyPayment);
document.getElementById('mc_loan_amount_display').innerHTML = formatter.format(loanAmount);
document.getElementById('mc_pi_display').innerHTML = formatter.format(monthlyPrincipalAndInterest);
document.getElementById('mc_tax_display').innerHTML = formatter.format(monthlyTax);
document.getElementById('mc_ins_display').innerHTML = formatter.format(monthlyInsurance);
document.getElementById('mc_hoa_display').innerHTML = formatter.format(monthlyHOA);
document.getElementById('mc_total_interest').innerHTML = formatter.format(totalInterest);
// Show Results
document.getElementById('mc_results').style.display = 'block';
}
Mortgage Calculator
Please enter valid positive numbers for all fields.
Total Monthly Payment
Loan Amount:
| Expense Breakdown | Amount |
|---|---|
| Principal & Interest | |
| Property Taxes (Monthly) | |
| Homeowners Insurance | |
| HOA Fees | |
| Total Interest Paid (Over Term) |
Understanding Your Mortgage Estimate
Purchasing a home is one of the most significant financial decisions you will make. This Mortgage Calculator is designed to provide you with a comprehensive view of your potential monthly housing costs, going beyond just the loan repayment to include taxes, insurance, and association fees.
The PITI Principle
When lenders calculate your ability to afford a home, they look at PITI: Principal, Interest, Taxes, and Insurance. It is crucial to understand that your check to the bank covers more than just paying back the loan.
- Principal: The portion of your payment that reduces the loan balance. In the early years, this is small.
- Interest: The cost of borrowing money. This makes up the bulk of your payments initially.
- Taxes: Property taxes charged by your local government, usually held in escrow by your lender.
- Insurance: Homeowners insurance to protect against damage, also typically held in escrow.
How Interest Rates Affect Your Payment
Even a small difference in interest rates can dramatically affect your monthly payment and the total cost of the loan. For example, on a $300,000 loan, a 1% increase in interest rate can add hundreds of dollars to your monthly payment and tens of thousands to the total repayment amount over 30 years.
Using This Calculator
To get the most accurate estimate, enter your expected home price and down payment. Don't forget to include estimates for Property Taxes and Home Insurance, as these vary by location. If you are buying a condo or a home in a managed community, be sure to add the HOA fees, as these are paid in addition to your mortgage but impact your monthly affordability.