Mortgage Calculator Australia
Compare fortnightly vs monthly repayments, model interest-only periods, stress-test rate rises, and see your loan balance shrink over time. Updated for 2025–26 Australian lending rates.
Your details
You're ahead by:
$159,450 in interest
5 years off the loan
Balance over time
Watch how each repayment reduces your balance and shifts more money from interest to principal.
What if rates rise?
Your repayments at the current rate vs. a 1% and 2% rate rise.
Amortization schedule
Year-by-year (or month-by-month) balance, principal paid, and interest paid for the entire loan term. Download as PDF below.
25 years
| Year | Principal | Interest | Balance |
|---|---|---|---|
| 1 | $10,894 | $36,879 | $589,106 |
| 2 | $11,590 | $36,183 | $577,516 |
| 3 | $12,330 | $35,442 | $565,186 |
| 4 | $13,118 | $34,655 | $552,068 |
| 5 | $13,956 | $33,817 | $538,113 |
| 6 | $14,847 | $32,925 | $523,265 |
| 7 | $15,796 | $31,977 | $507,469 |
| 8 | $16,805 | $30,968 | $490,664 |
| 9 | $17,879 | $29,894 | $472,786 |
| 10 | $19,021 | $28,752 | $453,765 |
| 11 | $20,236 | $27,537 | $433,529 |
| 12 | $21,529 | $26,244 | $412,000 |
| 13 | $22,904 | $24,869 | $389,096 |
| 14 | $24,367 | $23,405 | $364,729 |
| 15 | $25,924 | $21,849 | $338,805 |
| 16 | $27,580 | $20,193 | $311,225 |
| 17 | $29,342 | $18,431 | $281,884 |
| 18 | $31,216 | $16,556 | $250,667 |
| 19 | $33,211 | $14,562 | $217,457 |
| 20 | $35,332 | $12,440 | $182,125 |
| 21 | $37,589 | $10,183 | $144,535 |
| 22 | $39,991 | $7,782 | $104,545 |
| 23 | $42,545 | $5,227 | $61,999 |
| 24 | $45,263 | $2,509 | $16,736 |
| 25 | $16,736 | $205 | $0 |
Monthly view is approximated from yearly totals. Actual schedule depends on day-count and payment timing conventions used by your lender.
The fortnightly trick (the #1 way Australians pay off their mortgage faster)
Most banks quote your repayment as a monthly figure. But if you instead pay half that monthly amount every fortnight, something magical happens: there are 26 fortnights in a year, which means 26 × half-payments equals 13 full monthly equivalents per year, not 12.
You're paying one extra month per year, every year, with no change in your cash flow. On a $600,000 loan at 6.2%, this single switch saves ~5 years off your 30-year loan and roughly $145,000 in interest.
How this calculator works
We use the standard amortization formula that every Australian lender uses: M = P × [r(1+r)^n] / [(1+r)^n - 1]. Where you choose fortnightly or weekly, we apply the AU convention of paying the monthly amount divided by 2 (or 4) per period — this matches how the big four banks actually structure your repayments.
Worked example
A typical Sydney first-home buyer borrowing $600,000 with a $120,000 deposit at a 6.2% variable rate over 30 years:
- Monthly repayment: ~$3,677 → ~$1,323,650 total repaid
- Fortnightly equivalent: ~$1,838 → ~$1,180,000 total repaid (saves ~$143k)
- Plus $300 extra/month: cuts ~5 more years, saves ~$148k
Stress test your loan
The rate-rise stress test in the calculator above shows you what happens to your repayments at +1% and +2%. Australian lenders themselves stress-test all borrowers at the current rate plus 3% — that's the threshold APRA mandates to assess serviceability. If those numbers look uncomfortable, you might want a smaller loan, a longer term, or a bigger deposit.