let loanSteps = “”; const currencySymbol = “$”, fixedCurrency = “USD”; function calculateExtraPayment(){ loanSteps=””; const loanAmount = parseFloat(document.getElementById(“loanAmount”).value); const interestRate = parseFloat(document.getElementById(“interestRate”).value) / 100; const loanTerm = parseInt(document.getElementById(“loanTerm”).value); const extraPayment = parseFloat(document.getElementById(“extraPayment”).value); if (isNaN(loanAmount) || isNaN(interestRate) || isNaN(loanTerm) || isNaN(extraPayment) || loanAmount <= 0 || loanTerm <= 0 || interestRate <= 0) { alert("Please enter valid positive values for all fields."); return; } const monthlyPayment = loanAmount * (interestRate / 12) / (1 – Math.pow(1 + (interestRate / 12), -loanTerm)); const newLoanTerm = Math.ceil((Math.log((extraPayment / (extraPayment – monthlyPayment)) + 1) / Math.log(1 + interestRate / 12))); const totalInterest = (newLoanTerm * extraPayment) – loanAmount; document.getElementById("newLoanTerm").value = newLoanTerm; document.getElementById("totalInterest").value = formatCurrency(totalInterest); loanSteps += `Inputs:
Loan Amount: ${formatCurrency(loanAmount)}
Interest Rate: ${(interestRate * 100).toFixed(2)}%
Loan Term: ${loanTerm} months
Extra Payment: ${formatCurrency(extraPayment)}

`; loanSteps += `Results:
New Loan Term: ${newLoanTerm} months
Total Interest Paid: ${formatCurrency(totalInterest)}
`; if (document.getElementById(“calculationStepsLoan”).style.display === “block”) { document.getElementById(“calculationStepsLoan”).innerHTML = loanSteps; } } function resetAutoLoan(){ document.querySelectorAll(“#calculator input”).forEach(el => el.value = “”); loanSteps = “”; document.getElementById(“calculationStepsLoan”).innerHTML = “

Not calculated yet.

“; } function toggleLoanSteps(){ const s = document.getElementById(“calculationStepsLoan”); const a = document.getElementById(“toggleArrowLoan”); if (s.style.display === “none” || s.style.display === “”) { s.style.display = “block”; a.style.transform = “rotate(180deg)”; s.innerHTML = loanSteps || “

Not calculated yet.

“; } else { s.style.display = “none”; a.style.transform = “rotate(0deg)”; } } function formatCurrency(n) { return currencySymbol + n.toFixed(2) + ” ” + fixedCurrency; }