How is my mortgage repayment calculated?
Your repayment is calculated using the standard amortisation formula: P × [r(1+r)^n] ÷ [(1+r)^n − 1], where P is the principal, r is the periodic interest rate, and n is the total number of payments. Each repayment covers accrued interest first, then reduces the outstanding principal.
What's the difference between fortnightly and monthly repayments?
Fortnightly repayments result in 26 payments per year (equivalent to 13 monthly payments), which means you pay off your loan faster and save on total interest. Switching from monthly to fortnightly can cut years off a typical 30-year mortgage.
What does interest-only mean?
With an interest-only loan, your repayments cover only the interest charged each period — you don't pay down the principal. This results in lower repayments now but you'll owe the full original loan amount at the end of the interest-only period. Common among property investors for cash flow purposes.
What is the average Australian mortgage interest rate in 2026?
As of early 2026, the average Australian variable home loan rate sits around 5.5–6.5% depending on the lender and your loan-to-value ratio (LVR). Fixed rates vary more widely. Always compare rates from the major banks (CBA, ANZ, Westpac, NAB) as well as online lenders and brokers.
Does this calculator include other costs like stamp duty or LMI?
No — this calculator focuses purely on loan repayments. For stamp duty costs, use our Stamp Duty Calculator. Lenders Mortgage Insurance (LMI) typically applies when your deposit is less than 20% of the property value and can add thousands to your upfront costs.