Amortization Schedule
| Payment # |
Payment Amount |
Principal Payment |
Interest Payment |
Remaining Balance |
function calculateAmortization() {
const loanAmount = parseFloat(document.getElementById(“loanAmount”).value);
const interestRate = parseFloat(document.getElementById(“interestRate”).value) / 100 / 12;
const loanTerm = parseInt(document.getElementById(“loanTerm”).value) * 12;
const extraPayment = parseFloat(document.getElementById(“extraPayment”).value);
let monthlyPayment = (loanAmount * interestRate) / (1 – Math.pow(1 + interestRate, -loanTerm));
monthlyPayment += extraPayment;
let balance = loanAmount;
let paymentNumber = 0;
let tableBody = document.querySelector(“#scheduleTable tbody”);
tableBody.innerHTML = ”;
while (balance > 0) {
paymentNumber++;
const interestPayment = balance * interestRate;
const principalPayment = monthlyPayment – interestPayment;
if (balance < monthlyPayment) {
monthlyPayment = balance + interestPayment;
}
balance -= principalPayment;
const row = document.createElement("tr");
row.innerHTML = `
${paymentNumber} |
${monthlyPayment.toFixed(2)} |
${principalPayment.toFixed(2)} |
${interestPayment.toFixed(2)} |
${Math.max(balance, 0).toFixed(2)} |
`;
tableBody.appendChild(row);
}
}
