.mc-row { display: flex; flex-wrap: wrap; margin: 0 -10px; }
.mc-col { flex: 1; min-width: 250px; padding: 0 10px; margin-bottom: 20px; }
.mc-label { display: block; margin-bottom: 8px; font-weight: 600; color: #333; }
.mc-input { width: 100%; padding: 12px; border: 1px solid #ddd; border-radius: 4px; font-size: 16px; box-sizing: border-box; transition: border-color 0.3s; }
.mc-input:focus { border-color: #2c3e50; outline: none; }
.mc-btn { width: 100%; padding: 15px; background-color: #2c3e50; color: white; border: none; border-radius: 4px; font-size: 18px; font-weight: bold; cursor: pointer; transition: background-color 0.3s; }
.mc-btn:hover { background-color: #34495e; }
.mc-result-box { background-color: #f8f9fa; border: 1px solid #e9ecef; border-radius: 8px; padding: 25px; margin-top: 30px; text-align: center; display: none; }
.mc-result-value { font-size: 36px; color: #27ae60; font-weight: bold; margin: 10px 0; }
.mc-result-label { font-size: 14px; color: #666; text-transform: uppercase; letter-spacing: 1px; }
.mc-breakdown { display: flex; justify-content: space-between; margin-top: 20px; padding-top: 20px; border-top: 1px solid #ddd; text-align: left; }
.mc-breakdown-item { flex: 1; text-align: center; }
.mc-val-small { font-size: 18px; font-weight: 600; color: #333; }
/* SEO Content Styles */
.mc-content { margin-top: 50px; line-height: 1.6; color: #444; }
.mc-content h2 { color: #2c3e50; border-bottom: 2px solid #eee; padding-bottom: 10px; margin-top: 30px; }
.mc-content h3 { color: #2c3e50; margin-top: 25px; }
.mc-content ul { padding-left: 20px; }
.mc-content li { margin-bottom: 10px; }
function calculateMortgage() {
// Get input values using var
var homePrice = document.getElementById("mc-home-price").value;
var downPayment = document.getElementById("mc-down-payment").value;
var interestRate = document.getElementById("mc-interest-rate").value;
var loanTerm = document.getElementById("mc-loan-term").value;
// Validate inputs
if (homePrice === "" || downPayment === "" || interestRate === "") {
alert("Please fill in all fields with valid numbers.");
return;
}
// Parse values to floats
var priceVal = parseFloat(homePrice);
var downVal = parseFloat(downPayment);
var rateVal = parseFloat(interestRate);
var termVal = parseFloat(loanTerm);
// Basic logic validation
if (priceVal <= 0 || downVal < 0 || rateVal < 0) {
alert("Please enter positive values.");
return;
}
// Calculate Principal
var principal = priceVal – downVal;
// Handle case where down payment is greater than price
if (principal < 0) {
principal = 0;
}
// Calculate Monthly Interest Rate (r) and Total Months (n)
// r = annual rate / 100 / 12
var monthlyRate = (rateVal / 100) / 12;
var totalMonths = termVal * 12;
var monthlyPayment = 0;
// Calculate Monthly Payment using formula: M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1 ]
if (monthlyRate === 0) {
monthlyPayment = principal / totalMonths;
} else {
var numerator = monthlyRate * Math.pow(1 + monthlyRate, totalMonths);
var denominator = Math.pow(1 + monthlyRate, totalMonths) – 1;
monthlyPayment = principal * (numerator / denominator);
}
// Calculate Totals
var totalCost = monthlyPayment * totalMonths;
var totalInterest = totalCost – principal;
// Formatting currency
var formatter = new Intl.NumberFormat('en-US', {
style: 'currency',
currency: 'USD',
minimumFractionDigits: 2
});
var formatterNoDec = new Intl.NumberFormat('en-US', {
style: 'currency',
currency: 'USD',
minimumFractionDigits: 0,
maximumFractionDigits: 0
});
// Update DOM
document.getElementById("mc-monthly-payment").innerText = formatter.format(monthlyPayment);
document.getElementById("mc-total-principal").innerText = formatterNoDec.format(principal);
document.getElementById("mc-total-interest").innerText = formatterNoDec.format(totalInterest);
document.getElementById("mc-total-cost").innerText = formatterNoDec.format(totalCost);
// Show result box
document.getElementById("mc-result").style.display = "block";
}
Mortgage Payment Calculator
30 Years
20 Years
15 Years
10 Years
Estimated Monthly Payment
$0.00
Total Principal
$0
Total Interest
$0
Total Cost
$0
Understanding Your Mortgage Calculation
Buying a home is one of the most significant financial decisions you will make. This Mortgage Payment Calculator helps you estimate your monthly payments based on the home price, your down payment, the loan term, and the interest rate. By adjusting these variables, you can determine a budget that fits your financial lifestyle.
How the Formula Works
Mortgage amortization uses a specific formula to ensure that your payments remain consistent over the life of the loan, while the proportion of principal and interest changes over time. The standard formula used is:
M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1 ]
- 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 payments (Loan Term in years multiplied by 12)
Key Factors Affecting Your Monthly Payment
Several variables impact how much you pay each month and over the life of the loan:
- Down Payment: A larger down payment reduces your principal loan amount, lowering both your monthly payment and the total interest paid. Putting down at least 20% also typically avoids Private Mortgage Insurance (PMI).
- Interest Rate: Even a small difference in percentage points can drastically change the total cost of the loan. Rates are influenced by the economy, your credit score, and the loan type.
- Loan Term: A 30-year term offers lower monthly payments but results in higher total interest costs. Conversely, a 15-year term has higher monthly payments but saves significantly on interest.
Example Calculation
For example, if you purchase a home for $350,000 with a $70,000 (20%) down payment, your loan principal is $280,000. With a 30-year fixed rate of 6.5%:
- Your monthly principal and interest payment would be approximately $1,769.
- Over 30 years, you would pay a total of roughly $637,000, meaning $357,000 goes purely toward interest.
Use the calculator above to run your own scenarios and plan your home purchase effectively.