Loan amount
$720,000 AusTax Loan Tools Stage 1 of 4: Start
Mortgage repayment calculator
Calculate principal and interest repayments by frequency before locking your borrowing range.
Repayment workbench
Mortgage repayment calculator
Model repayments, interest, and payoff timeline before locking your borrowing range.
Snapshot
LVR
80.00%Monthly repayment
$4,363Total interest
$850,738Estimated payoff
30.00 yrsYears saved
0.00 yrsInterest saved vs baseline
$0Payoff years saved vs baseline
0.00 yrsAmortization preview
First 18 periods
Period 1
$4,363Interest $3,660 | Principal $703Balance $719,297Period 2
$4,363Interest $3,656 | Principal $707Balance $718,590Period 3
$4,363Interest $3,653 | Principal $710Balance $717,880Period 4
$4,363Interest $3,649 | Principal $714Balance $717,166Period 5
$4,363Interest $3,646 | Principal $718Balance $716,448Period 6
$4,363Interest $3,642 | Principal $721Balance $715,727| Period | Payment | Interest | Principal | Balance |
|---|---|---|---|---|
| 1 | $4,363 | $3,660 | $703 | $719,297 |
| 2 | $4,363 | $3,656 | $707 | $718,590 |
| 3 | $4,363 | $3,653 | $710 | $717,880 |
| 4 | $4,363 | $3,649 | $714 | $717,166 |
| 5 | $4,363 | $3,646 | $718 | $716,448 |
| 6 | $4,363 | $3,642 | $721 | $715,727 |
| 7 | $4,363 | $3,638 | $725 | $715,002 |
| 8 | $4,363 | $3,635 | $729 | $714,274 |
| 9 | $4,363 | $3,631 | $732 | $713,541 |
| 10 | $4,363 | $3,627 | $736 | $712,805 |
| 11 | $4,363 | $3,623 | $740 | $712,066 |
| 12 | $4,363 | $3,620 | $743 | $711,322 |
| 13 | $4,363 | $3,616 | $747 | $710,575 |
| 14 | $4,363 | $3,612 | $751 | $709,824 |
| 15 | $4,363 | $3,608 | $755 | $709,069 |
| 16 | $4,363 | $3,604 | $759 | $708,310 |
| 17 | $4,363 | $3,601 | $763 | $707,548 |
| 18 | $4,363 | $3,597 | $766 | $706,781 |
Check the drag, not just the payment
Total interest and payoff horizon show whether a "comfortable" repayment is quietly locking you into a weak long-term position.
Model realistic commitment
Extra repayments only matter if they are sustainable. Test the version of your budget that survives normal life noise, not the perfect month.
Use this as the baseline
This page should establish the baseline number. The next move is stress testing, not assuming today's repayment will stay comfortable.
Action thresholds from your repayment output
Green
Repayment leaves room for buffer and future rate increases. Proceed to rate-stress validation.
Amber
Repayment is manageable but tight. Reduce loan size or extend planning buffer before progressing.
Red
Repayment crowds out essentials or savings. Rework budget assumptions before seeking quotes.
Upfront cash check
Repayments matter, but buyers still need the stamp duty cash
This calculator shows ongoing repayments only. If you are buying, add your state stamp duty and registration fees next so your total cash requirement matches the property price you are testing.
A real purchase budget is not just deposit plus repayments. It also includes stamp duty, transfer registration, and mortgage registration before settlement.
NSW stamp duty
Transfer duty and upfront costs
VIC stamp duty
Land transfer duty by buyer type
QLD stamp duty
Home concession and investor rates
SA stamp duty
Transfer duty and registration fees
WA stamp duty
General duty and settlement costs
TAS stamp duty
Duty estimate for Tasmania purchases
ACT stamp duty
Owner-occupier and investor duty
NT stamp duty
Duty plus transfer and mortgage fees
First home buyer? Check the state-specific concession and exemption pages from the main stamp duty calculator once you choose your state.
Math to decisions
A repayment number is useful only when it survives stress.
Use this calculator as your baseline, then pressure-test and score options before choosing a loan path.
Run rate stress testRelated Mortgage tools
FAQs
How do I calculate mortgage repayments in Australia?
Use loan amount, interest rate, loan term and repayment frequency in a principal-and-interest repayment formula.
Is monthly or fortnightly repayment better?
Fortnightly can reduce interest over time because payments are applied more frequently, but impact depends on lender setup and calendar handling.
Does this calculator include fees and stamp duty?
No. This calculator focuses on principal and interest. Include purchase and ongoing property costs separately.