Loan Payment Calculator
body {
font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
background-color: #eef2f7;
color: #333;
line-height: 1.6;
margin: 0;
padding: 20px;
display: flex;
justify-content: center;
align-items: flex-start;
min-height: 100vh;
}
.loan-calc-container {
background-color: #ffffff;
padding: 30px;
border-radius: 8px;
box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
width: 100%;
max-width: 700px;
box-sizing: border-box;
}
h1, h2 {
color: #004a99;
text-align: center;
margin-bottom: 25px;
}
.input-group {
margin-bottom: 20px;
display: flex;
flex-direction: column;
}
.input-group label {
margin-bottom: 8px;
font-weight: bold;
color: #004a99;
}
.input-group input[type="number"],
.input-group input[type="range"] {
padding: 12px;
border: 1px solid #ccc;
border-radius: 4px;
font-size: 1rem;
width: 100%;
box-sizing: border-box;
}
.input-group input[type="range"] {
cursor: pointer;
}
button {
background-color: #004a99;
color: white;
padding: 12px 20px;
border: none;
border-radius: 4px;
font-size: 1.1rem;
cursor: pointer;
transition: background-color 0.3s ease;
width: 100%;
margin-top: 10px;
}
button:hover {
background-color: #003366;
}
#result {
margin-top: 30px;
padding: 20px;
background-color: #28a745;
color: white;
border-radius: 4px;
text-align: center;
font-size: 1.8rem;
font-weight: bold;
box-shadow: 0 2px 8px rgba(40, 167, 69, 0.4);
}
#result span {
font-size: 1rem;
font-weight: normal;
display: block;
margin-top: 5px;
}
.explanation {
margin-top: 40px;
padding: 25px;
background-color: #f8f9fa;
border: 1px solid #e0e0e0;
border-radius: 8px;
}
.explanation h2 {
color: #004a99;
text-align: left;
margin-bottom: 15px;
}
.explanation p, .explanation ul {
margin-bottom: 15px;
color: #555;
}
.explanation li {
margin-bottom: 8px;
}
.explanation strong {
color: #004a99;
}
@media (max-width: 600px) {
.loan-calc-container {
padding: 20px;
}
h1 {
font-size: 1.8rem;
}
button {
font-size: 1rem;
}
#result {
font-size: 1.5rem;
}
}
Loan Payment Calculator
Loan Amount ($)
Annual Interest Rate (%)
Loan Term (Years)
Calculate Monthly Payment
Monthly Payment: Total Principal Paid:
Total Interest Paid:
Total Amount Paid:
Understanding Your Loan Payments
This calculator helps you estimate the monthly payment for a fixed-rate loan. Understanding these figures is crucial for budgeting and making informed financial decisions.
How the Calculation Works:
The formula used is the standard annuity formula for calculating the monthly payment (M) of a loan:
M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1]
Where:
P = Principal loan amount (the total amount borrowed)i = Monthly interest rate (Annual interest rate / 12 / 100)n = Total number of payments (Loan term in years * 12)
The calculator also computes:
Total Principal Paid : This is simply the original loan amount (P).Total Interest Paid : Calculated as (Monthly Payment * Total Number of Payments) – Principal Loan Amount.Total Amount Paid : Calculated as Monthly Payment * Total Number of Payments.
Key Terms Explained:
Loan Amount (Principal) : The initial sum of money you borrow.Annual Interest Rate : The yearly percentage charged by the lender on the outstanding loan balance.Loan Term : The duration over which you will repay the loan, expressed in years.Monthly Payment : The fixed amount you pay each month towards the loan, covering both principal and interest.
Use Cases:
This calculator is useful for:
Estimating monthly payments for mortgages, auto loans, personal loans, student loans, and more.
Comparing different loan offers with varying interest rates and terms.
Budgeting for new or existing loans.
Understanding the total cost of borrowing over the life of the loan.
Please note that this is an estimate. Actual loan payments may vary based on lender fees, payment schedules, and specific loan terms.
function calculateLoanPayment() {
var loanAmount = parseFloat(document.getElementById("loanAmount").value);
var annualInterestRate = parseFloat(document.getElementById("interestRate").value);
var loanTerm = parseFloat(document.getElementById("loanTerm").value);
var resultDiv = document.getElementById("result");
var monthlyPaymentValueSpan = document.getElementById("monthlyPaymentValue");
var totalPrincipalValueSpan = document.getElementById("totalPrincipalValue");
var totalInterestValueSpan = document.getElementById("totalInterestValue");
var totalAmountPaidValueSpan = document.getElementById("totalAmountPaidValue");
if (isNaN(loanAmount) || isNaN(annualInterestRate) || isNaN(loanTerm) || loanAmount <= 0 || annualInterestRate < 0 || loanTerm <= 0) {
alert("Please enter valid positive numbers for all fields.");
resultDiv.style.display = 'none';
return;
}
var monthlyInterestRate = (annualInterestRate / 100) / 12;
var numberOfPayments = loanTerm * 12;
var monthlyPayment;
if (monthlyInterestRate === 0) {
monthlyPayment = loanAmount / numberOfPayments;
} else {
monthlyPayment = loanAmount * (monthlyInterestRate * Math.pow(1 + monthlyInterestRate, numberOfPayments)) / (Math.pow(1 + monthlyInterestRate, numberOfPayments) – 1);
}
var totalInterestPaid = (monthlyPayment * numberOfPayments) – loanAmount;
var totalAmountPaid = monthlyPayment * numberOfPayments;
monthlyPaymentValueSpan.textContent = "$" + monthlyPayment.toFixed(2);
totalPrincipalValueSpan.textContent = "$" + loanAmount.toFixed(2);
totalInterestValueSpan.textContent = "$" + totalInterestPaid.toFixed(2);
totalAmountPaidValueSpan.textContent = "$" + totalAmountPaid.toFixed(2);
resultDiv.style.display = 'block';
}