Australian Mortgage Calculator with Offset, Extra Repayments & Goal Seeker

What this calculator does

• Calculates weekly, fortnightly or monthly repayments using the standard amortising mortgage formula
• Supports variable, fixed and introductory loan types with rate-revert phases
• Models offset accounts and ongoing deposits — see when your interest charged hits $0
• Estimates stamp duty + transfer fees for NSW, VIC, QLD, WA, SA, TAS, ACT and NT
• Calculates Loan-to-Value Ratio (LVR) and warns when LMI applies (above 80%)
• Compares principal-and-interest vs interest-only repayment types
• Goal seeker: tell it your target payoff year and it works out the contribution needed
• Rate sensitivity table: see what happens to your repayment if rates move ±2%
• Full year-by-year amortisation schedule with CSV download

Frequently asked questions

How is my mortgage repayment calculated?

Using the standard amortising formula M = P × r × (1+r)ⁿ / ((1+r)ⁿ − 1). The periodic rate is the annual rate divided by 12 (monthly), 26 (fortnightly) or 52 (weekly) — the same convention every major Australian lender and ASIC MoneySmart uses.

How does an offset account work?

Money sitting in a linked offset account is subtracted from your loan balance before interest is calculated each period. The cash stays accessible, but every dollar in offset is a dollar you don't pay interest on.

How much stamp duty will I pay?

Stamp duty depends on the property price and the state or territory. This calculator uses up-to-date bracket tables for all eight Australian jurisdictions and includes an estimated land transfer fee on top.