Mortgage Repayment Calculator
See the true impact of extra repayments & your offset account — using the same interest calculation methodology as Australian lenders.
🏠 Loan Details
$
yrs
% p.a.
$
➕ Additional Repayments
$
🏠 Offset Account
$
💡 How offset works: Your offset balance reduces the amount interest is charged on each period — your repayment stays the same, so more reduces your principal. Example: $850,000 loan with $100,000 offset → interest charged on $750,000 only.
📊 Your Results
Four scenarios compared side by side based on your inputs
🏠
-
Offset Saves
(Interest)
(Interest)
⏱
-
Offset Saves
(Time)
(Time)
💰
-
Extra Repayments
Save (Interest)
Save (Interest)
📅
-
Extra Repayments
Save (Time)
Save (Time)
🎉
-
Combined Strategy
Saves (Interest)
Saves (Interest)
✅
-
Combined Strategy
Saves (Time)
Saves (Time)
Base Scenario
-
Loan Term
Total Interest-
Total Repaid-
Interest on Balance-
Offset Account Only
-
Loan Term
Total Interest-
Total Repaid-
Interest on Balance-
-Extra Repayments Only
-
Loan Term
Total Interest-
Total Repaid-
Interest on Balance-
-Combined Strategy
-
Loan Term
Total Interest-
Total Repaid-
Interest on Balance-
-📉 Loan Balance Over Time
Outstanding balance year by year across all four scenarios
💵 Total Interest Comparison
Total interest paid across all four scenarios
📊 Cumulative Interest Paid Over Time
How your total interest cost grows differently under each strategy
📋 Full Scenario Comparison
| Scenario | Loan Term | Total Interest | Total Repaid | Interest Saved | Time Saved |
|---|
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ℹ️ Calculation methodology: Uses the nominal periodic rate (annual rate ÷ periods per year), consistent with MoneySmart, CommBank and Australian lender standards.
This calculator is for illustrative purposes only and does not constitute financial advice. Results assume a constant interest rate and consistent repayments throughout the loan term. Calculations use the nominal periodic interest rate (annual rate ÷ periods per year) consistent with Australian lending standards. Please consult a licensed financial adviser for personalised guidance.
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