.calculator-widget-container {
font-family: 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
max-width: 800px;
margin: 0 auto;
background: #ffffff;
border: 1px solid #e0e0e0;
border-radius: 8px;
box-shadow: 0 4px 6px rgba(0,0,0,0.05);
padding: 20px;
}
.calc-header {
text-align: center;
margin-bottom: 30px;
background-color: #2c3e50;
color: white;
padding: 15px;
border-radius: 6px;
}
.calc-header h2 {
margin: 0;
font-size: 24px;
}
.calc-grid {
display: grid;
grid-template-columns: 1fr 1fr;
gap: 20px;
}
@media (max-width: 600px) {
.calc-grid {
grid-template-columns: 1fr;
}
}
.input-group {
margin-bottom: 15px;
}
.input-group label {
display: block;
margin-bottom: 5px;
font-weight: 600;
color: #34495e;
font-size: 14px;
}
.input-wrapper {
position: relative;
display: flex;
align-items: center;
}
.input-prefix, .input-suffix {
background: #f1f2f6;
padding: 10px 12px;
border: 1px solid #dcdcdc;
color: #7f8c8d;
font-size: 14px;
}
.input-prefix {
border-right: none;
border-radius: 4px 0 0 4px;
}
.input-suffix {
border-left: none;
border-radius: 0 4px 4px 0;
}
.calc-input {
width: 100%;
padding: 10px;
border: 1px solid #dcdcdc;
font-size: 16px;
outline: none;
transition: border-color 0.3s;
}
.calc-input:focus {
border-color: #3498db;
}
.calc-input.has-prefix {
border-radius: 0 4px 4px 0;
}
.calc-input.has-suffix {
border-radius: 4px 0 0 4px;
}
.calc-input.has-both {
border-radius: 0;
}
.calc-btn {
grid-column: 1 / -1;
background-color: #27ae60;
color: white;
border: none;
padding: 15px;
font-size: 18px;
font-weight: bold;
border-radius: 5px;
cursor: pointer;
transition: background-color 0.3s;
margin-top: 10px;
width: 100%;
}
.calc-btn:hover {
background-color: #219150;
}
.results-section {
margin-top: 30px;
padding-top: 20px;
border-top: 2px solid #f1f2f6;
display: none;
}
.results-grid {
display: grid;
grid-template-columns: 1fr 1fr;
gap: 20px;
}
.result-card {
background: #f8f9fa;
padding: 15px;
border-radius: 6px;
text-align: center;
border-left: 4px solid #3498db;
}
.result-card.main-result {
grid-column: 1 / -1;
background: #e8f6f3;
border-left: 4px solid #27ae60;
}
.result-label {
font-size: 13px;
color: #7f8c8d;
text-transform: uppercase;
letter-spacing: 1px;
margin-bottom: 5px;
}
.result-value {
font-size: 24px;
font-weight: 800;
color: #2c3e50;
}
.main-result .result-value {
font-size: 36px;
color: #27ae60;
}
.breakdown-list {
list-style: none;
padding: 0;
margin-top: 20px;
}
.breakdown-list li {
display: flex;
justify-content: space-between;
padding: 10px 0;
border-bottom: 1px solid #eee;
font-size: 14px;
}
.breakdown-list li:last-child {
border-bottom: none;
}
.seo-content {
margin-top: 50px;
line-height: 1.6;
color: #333;
}
.seo-content h2 {
color: #2c3e50;
border-bottom: 2px solid #eee;
padding-bottom: 10px;
margin-top: 30px;
}
.seo-content h3 {
color: #34495e;
margin-top: 25px;
}
.seo-content p {
margin-bottom: 15px;
}
.seo-content ul {
margin-bottom: 15px;
padding-left: 20px;
}
.error-msg {
color: #e74c3c;
text-align: center;
margin-top: 10px;
font-weight: bold;
display: none;
}
// Sync logic: When User changes %, update $
function updateDownPaymentAmount() {
var price = parseFloat(document.getElementById('homePrice').value) || 0;
var percent = parseFloat(document.getElementById('downPaymentPercent').value) || 0;
var amount = price * (percent / 100);
document.getElementById('downPaymentAmount').value = amount.toFixed(0);
}
// Sync logic: When User changes $, update %
function updateDownPaymentPercent() {
var price = parseFloat(document.getElementById('homePrice').value) || 0;
var amount = parseFloat(document.getElementById('downPaymentAmount').value) || 0;
if (price > 0) {
var percent = (amount / price) * 100;
document.getElementById('downPaymentPercent').value = percent.toFixed(2);
}
}
// Sync logic: When Home Price changes, keep the % constant and update $
function syncDownPaymentValues() {
updateDownPaymentAmount();
}
function calculateMortgage() {
// 1. Get Inputs
var homePrice = parseFloat(document.getElementById('homePrice').value);
var downPayment = parseFloat(document.getElementById('downPaymentAmount').value);
var interestRate = parseFloat(document.getElementById('interestRate').value);
var loanTermYears = parseFloat(document.getElementById('loanTerm').value);
var yearlyTax = parseFloat(document.getElementById('propertyTax').value);
var yearlyInsurance = parseFloat(document.getElementById('homeInsurance').value);
var monthlyHOA = parseFloat(document.getElementById('hoaFees').value);
var errorDiv = document.getElementById('errorDisplay');
var resultsDiv = document.getElementById('resultsSection');
// 2. Validation
if (isNaN(homePrice) || isNaN(downPayment) || isNaN(interestRate) || isNaN(loanTermYears)) {
errorDiv.style.display = 'block';
errorDiv.innerHTML = "Please enter valid numbers for all required fields.";
resultsDiv.style.display = 'none';
return;
}
if (downPayment >= homePrice) {
errorDiv.style.display = 'block';
errorDiv.innerHTML = "Down payment cannot be equal to or greater than the home price.";
resultsDiv.style.display = 'none';
return;
}
errorDiv.style.display = 'none';
resultsDiv.style.display = 'block';
// 3. Calculation Logic
var principal = homePrice – downPayment;
var monthlyInterestRate = (interestRate / 100) / 12;
var numberOfPayments = loanTermYears * 12;
// Mortgage Formula: M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1 ]
var monthlyPrincipalInterest = 0;
if (interestRate === 0) {
monthlyPrincipalInterest = principal / numberOfPayments;
} else {
var mathPow = Math.pow(1 + monthlyInterestRate, numberOfPayments);
monthlyPrincipalInterest = principal * ((monthlyInterestRate * mathPow) / (mathPow – 1));
}
var monthlyTax = yearlyTax / 12;
var monthlyInsurance = yearlyInsurance / 12;
var totalMonthlyPayment = monthlyPrincipalInterest + monthlyTax + monthlyInsurance + monthlyHOA;
var totalCostOfLoan = (monthlyPrincipalInterest * numberOfPayments);
var totalInterestPaid = totalCostOfLoan – principal;
// Calculate Payoff Date
var today = new Date();
today.setMonth(today.getMonth() + numberOfPayments);
var options = { year: 'numeric', month: 'long' };
var payoffDateString = today.toLocaleDateString("en-US", options);
// 4. Update UI with formatted numbers
var currencyFormatter = new Intl.NumberFormat('en-US', {
style: 'currency',
currency: 'USD',
minimumFractionDigits: 2
});
document.getElementById('totalMonthlyPayment').innerText = currencyFormatter.format(totalMonthlyPayment);
document.getElementById('piPayment').innerText = currencyFormatter.format(monthlyPrincipalInterest);
document.getElementById('loanAmountResult').innerText = currencyFormatter.format(principal);
document.getElementById('totalInterestResult').innerText = currencyFormatter.format(totalInterestPaid);
document.getElementById('payoffDate').innerText = payoffDateString;
// Breakdown updates
document.getElementById('breakdownPI').innerText = currencyFormatter.format(monthlyPrincipalInterest);
document.getElementById('breakdownTax').innerText = currencyFormatter.format(monthlyTax);
document.getElementById('breakdownInsurance').innerText = currencyFormatter.format(monthlyInsurance);
document.getElementById('breakdownHOA').innerText = currencyFormatter.format(monthlyHOA);
}
Advanced Mortgage Calculator
$
%
%
$
Years
$
$
$
Total Monthly Payment
$0.00
Principal & Interest
$0.00
Loan Amount
$0.00
Total Interest Paid
$0.00
Payoff Date
–
Monthly Breakdown
- Principal & Interest: $0.00
- Property Tax: $0.00
- Home Insurance: $0.00
- HOA Fees: $0.00
Understanding Your Mortgage Calculation
Purchasing a home is likely the largest financial commitment you will make in your lifetime. Understanding how your monthly mortgage payment is calculated is crucial for maintaining financial health. This Mortgage Calculator is designed to give you a comprehensive view of your monthly housing costs, going beyond just the loan repayment.
The 4 Pillars of a Mortgage Payment (PITI)
When lenders look at your ability to pay, they typically look at PITI: Principal, Interest, Taxes, and Insurance.
- Principal: The portion of your payment that goes toward reducing the loan balance. In the early years of a 30-year mortgage, this amount is small, but it grows over time.
- Interest: The cost of borrowing money. Initially, the majority of your payment goes here. A lower interest rate can save you tens of thousands of dollars over the life of the loan.
- Taxes: Property taxes are usually collected by your lender in an escrow account and paid annually to your local government. These are based on your home's assessed value.
- Insurance: Homeowners insurance protects your property against damage. Like taxes, this is often bundled into your monthly payment via escrow.
How Down Payments Affect Your Loan
Your down payment significantly influences your mortgage terms. Putting down at least 20% typically removes the need for Private Mortgage Insurance (PMI), which protects the lender if you default. In our calculator, adjusting the "Down Payment" field immediately updates your "Loan Amount" and "Total Interest Paid" projections. A larger down payment reduces the principal, thereby lowering both your monthly payment and total interest costs.
HOA Fees and Total Affordability
Many homebuyers forget to factor in Homeowners Association (HOA) fees. While these fees generally don't cover the loan itself, they are a mandatory monthly expense for condos and many planned communities. Our calculator includes a specific field for HOA fees to ensure your "Total Monthly Payment" reflects the true cost of homeownership.
Interpreting the Results
Total Interest Paid: This figure often shocks new buyers. Over a 30-year term, you might pay nearly as much in interest as you did for the house itself. Seeing this number might encourage you to look for a shorter loan term (e.g., 15 years) or make extra principal payments.
Payoff Date: This estimates when you will be mortgage-free, assuming you make standard payments consistently starting from today.
Tips for Lowering Your Payment
- Boost your credit score: Higher scores qualify for lower interest rates.
- Shop around: Even a 0.5% difference in rate makes a massive impact.
- Increase your down payment: Reduces principal and avoids PMI.
- Consider a shorter term: 15-year mortgages have higher monthly payments but significantly lower interest rates and total costs.