Home Building Loan Calculator Australia

Home Building Loan Calculator (Australia)

Estimate your home loan repayments and total interest with our easy-to-use home building loan calculator.

Loan Amount ($) Interest Rate (%) Loan Term (Years) Estimated Monthly Repayment ($) Total Interest ($) Total Repayment ($) let loanSteps = “”; function calculateLoan(){ loanSteps = “”; const loanAmount = parseFloat(document.getElementById(“loanAmount”).value); const interestRate = parseFloat(document.getElementById(“interestRate”).value) / 100 / 12; const loanTerm = parseInt(document.getElementById(“loanTerm”).value) * 12; if(isNaN(loanAmount) || isNaN(interestRate) || isNaN(loanTerm) || loanAmount <= 0 || interestRate <= 0 || loanTerm <= 0){ alert("Please enter valid positive values for all fields."); return; } const monthlyRepayment = (loanAmount * interestRate) / (1 – Math.pow(1 + interestRate, -loanTerm)); const totalRepayment = monthlyRepayment * loanTerm; const totalInterest = totalRepayment – loanAmount; document.getElementById("monthlyRepayment").value = formatCurrency(monthlyRepayment); document.getElementById("totalRepayment").value = formatCurrency(totalRepayment); document.getElementById("totalInterest").value = formatCurrency(totalInterest); loanSteps += `Inputs:
Loan Amount: ${formatCurrency(loanAmount)}
Interest Rate: ${(interestRate * 100 * 12).toFixed(2)}%
Loan Term: ${loanTerm / 12} years

`; loanSteps += `Formulas:
Monthly Repayment = Loan Amount × Interest Rate ÷ (1 – (1 + Interest Rate)^(-Loan Term))
Total Repayment = Monthly Repayment × Loan Term
Total Interest = Total Repayment – Loan Amount

`; loanSteps += `Results:
Monthly Repayment: ${formatCurrency(monthlyRepayment)}
Total Repayment: ${formatCurrency(totalRepayment)}
Total Interest: ${formatCurrency(totalInterest)}
`; if(document.getElementById(“calculationStepsLoan”).style.display === “block”){ document.getElementById(“calculationStepsLoan”).innerHTML = loanSteps; } } function resetLoan(){ document.querySelectorAll(“#homeBuildingLoanForm 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 “$” + n.toFixed(2); }