Estimate your mortgage repayments in seconds with clear, practical scenario modelling. Compare Principal & Interest vs Interest Only, test different rates and terms, add upfront and ongoing fees, and apply extra repayments to see how quickly your balance can reduce. You can also include an offset balance to estimate interest savings and view how each change affects repayments, total interest, and overall loan cost over time.
Built for Australian home loans, with clear repayments and term-based cost breakdowns.
Loan details
Repayment frequency
Repayment type
Fees
Extra repayments
See how small extra payments can reduce your loan
+$100/mo → Save 2.2 years • Save $67,163 interest
+$200/mo → Save 4.0 years • Save $121,989 interest
+$400/mo → Save 6.9 years • Save $206,898 interest
Offset account
Repayment
Frequency selected: Monthly
Interest charged first month: $3,250.00
Average interest per month (over loan term): $2,125.74
Total interest by repayment frequency
If weekly: $764,348 ($919 less than monthly)
If fortnightly: $764,623 ($643 less than monthly)
Total interest
$765,267
Total fees
$0
Total cost
$1,365,267
Rate stress test reminder
InfoTotal interest context
NoteShare your current inputs and results with a deep link.
Results are estimates only and may differ from lender calculations. This information is general and not financial advice.
| Year | Starting balance | Ending balance | Interest paid | Principal paid |
|---|---|---|---|---|
| 1 | $600,000 | $593,294 | $38,803 | $6,706 |
| 2 | $593,294 | $586,138 | $38,353 | $7,155 |
| 3 | $586,138 | $578,503 | $37,874 | $7,635 |
| 4 | $578,503 | $570,357 | $37,363 | $8,146 |
| 5 | $570,357 | $561,666 | $36,817 | $8,692 |
| 6 | $561,666 | $552,392 | $36,235 | $9,274 |
| 7 | $552,392 | $542,497 | $35,614 | $9,895 |
| 8 | $542,497 | $531,940 | $34,952 | $10,557 |
| 9 | $531,940 | $520,676 | $34,244 | $11,264 |
| 10 | $520,676 | $508,657 | $33,490 | $12,019 |
| 11 | $508,657 | $495,833 | $32,685 | $12,824 |
| 12 | $495,833 | $482,150 | $31,826 | $13,683 |
| 13 | $482,150 | $467,551 | $30,910 | $14,599 |
| 14 | $467,551 | $451,975 | $29,932 | $15,577 |
| 15 | $451,975 | $435,355 | $28,889 | $16,620 |
| 16 | $435,355 | $417,622 | $27,776 | $17,733 |
| 17 | $417,622 | $398,701 | $26,588 | $18,921 |
| 18 | $398,701 | $378,514 | $25,321 | $20,188 |
| 19 | $378,514 | $356,974 | $23,969 | $21,540 |
| 20 | $356,974 | $333,992 | $22,527 | $22,982 |
| 21 | $333,992 | $309,470 | $20,987 | $24,521 |
| 22 | $309,470 | $283,307 | $19,345 | $26,164 |
| 23 | $283,307 | $255,391 | $17,593 | $27,916 |
| 24 | $255,391 | $225,605 | $15,723 | $29,785 |
| 25 | $225,605 | $193,825 | $13,729 | $31,780 |
| 26 | $193,825 | $159,916 | $11,600 | $33,909 |
| 27 | $159,916 | $123,737 | $9,329 | $36,180 |
| 28 | $123,737 | $85,134 | $6,906 | $38,603 |
| 29 | $85,134 | $43,946 | $4,321 | $41,188 |
| 30 | $43,946 | $0 | $1,563 | $43,946 |
| Totals | — | $0 | $765,267 | $600,000 |
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Interest is generally calculated on your loan balance minus your offset balance. A larger offset can reduce interest over time when the offset remains in place.
A mortgage calculator Australia tool is most useful when you treat it as a decision framework, not just a single repayment output. A typical home loan spans decades, so small differences in rate, term, fees, offset balance, and repayment frequency can produce large differences in total cost. This page is built to show those tradeoffs clearly. You can test scenarios quickly, then narrow to options that suit your monthly cash flow and long-term interest objectives.
Home loan repayments are driven by three core inputs: principal, interest rate, and loan term. Frequency then changes how repayments are distributed through your budget. Weekly and fortnightly amounts can improve day-to-day cash visibility, while monthly views align with many household bills. If you are still confirming your purchase range, start with the borrowing capacity calculator first, then return here to validate whether repayments still feel sustainable under your preferred term and rate assumptions.
Interest rate comparison is one of the highest-impact steps in loan planning. Even modest changes can materially alter both repayments and lifetime interest. A practical method is to run a base scenario, then stress-test +0.50% and +1.00% cases to understand downside risk. You can complement this with the RBA Cash Rate page for macro context. While variable mortgage pricing does not move one-for-one with the official rate, policy direction can help frame realistic scenario ranges.
The amortisation schedule matters because it explains where your money goes each period. Early repayments are usually interest-heavy, with principal reduction accelerating over time. This is why offset account balances and extra repayments can improve outcomes disproportionately in earlier years. If you also evaluate investment pathways, compare repayment structure here with the investment property calculator to separate owner-occupier repayment planning from rental cash flow and tax-focused scenarios.
Switching the chart to cumulative mode shows your cumulative interest (running interest total), which makes it easier to compare long-term cost across different rate, term, and extra-repayment scenarios.
Example query: "mortgage calculator Australia 30 year fixed vs variable estimate." Start with the same loan amount and term in two scenarios, then vary only the interest rate and any monthly fees. Review repayment, yearly interest, and total cost, then cross-check the comparison rate from lenders for like-for-like screening. Next, add a modest ongoing extra repayment to each scenario and compare the change in estimated payoff time. This method helps identify whether a slightly higher repayment today may materially reduce total interest over the loan horizon, while still staying within your practical cash-flow limits.
Calculator outputs are estimates and should be interpreted alongside lender policy, product terms, and your full financial position. Rounding approaches, fee treatment, and assessment rules can vary by institution. Use this page to shortlist viable structures, then confirm details with a lender or broker before commitment. A strong process is: estimate borrowing range, compare repayment scenarios, stress-test rates, and only then proceed to formal product selection. This sequence supports clearer decisions and reduces avoidable repayment surprises later.
For definitions of key loan terms, visit the Finance Glossary and compare your scenario with the personal loan calculator where loan interest calculator assumptions differ by product type.
LoanMetric estimates home loan repayments using standard amortisation principles commonly used in finance.
Estimates only. Not financial advice or a credit offer.