Home loan repayment calculator

We take your loan balance, interest rate, and remaining term, then layer in your extra repayment amount and frequency. The model recalculates the daily interest accrual based on the lower balance and projects how much earlier the loan is paid off and how much total interest you save. The result isolates the impact of the extra repayments from the rest of your repayment schedule.

At 6.5%, every dollar of principal reduction saves about 2.6× more interest per year than it did at 2.5%. On a $500,000 loan at 6.5%, an extra $50 per fortnight saves roughly $78,000 in interest and cuts about 4 years off the term. On an $800,000 loan, $200 per month saves around $175,000 and trims 5 years. The earlier in the loan you start, the bigger the compounding benefit.

If part of your loan is fixed, check the annual cap on extra repayments — most fixed loans limit extras to $10,000–$30,000 per year before break costs apply. Variable loans almost always allow unlimited extras. Also confirm whether your lender treats the extra as principal reduction or as a redraw buffer; both reduce interest, but redraw funds remain accessible if you need them back.