The Debt Payoff Calculator loads your mortgages, investment loans, HECS, credit cards, and personal loans and shows you when each one will be paid off — and what happens when you put extra money toward repayments.
What it does
For every liability on your account, the calculator:
- Uses the loan terms you’ve already captured (interest rate, repayment amount, repayment frequency, loan type).
- Shows the result of continuing with your current repayments as Do nothing.
- Compares Avalanche, Snowball and Proportional when you enter an extra monthly amount, then recommends the fastest result with total interest as the tie-breaker.
- Turns the recommended strategy into a staged repayment plan that names the debt to target, the monthly amount to pay, the expected payoff time and where to redirect that repayment next.
- Shows the strategies side-by-side before taking you to the full debt trajectory.
Repayment strategies
| Strategy | How it works |
|---|---|
| Avalanche | Puts all extra repayment toward your highest-interest loan first. When that loan is paid off, the freed amount cascades into the next-highest-rate loan automatically. Mathematically minimises the total interest you pay. |
| Snowball | Puts extra toward your smallest balance first. When that loan is gone, the freed amount cascades into the next-smallest balance. Produces quick wins by closing accounts early. |
| Proportional | Splits your extra amount across all loans in proportion to their current balances. Neutral; useful when you can’t decide or want a balanced approach. |
| Manual | You decide exactly how much extra to put toward each loan individually. Once a chosen debt is cleared, its freed repayment moves to the highest-rate remaining debt. |
All strategies automatically roll over freed cashflow — when a loan pays off, both its regular repayment and extra allocation cascade to the next-priority loan so your full repayment budget stays deployed.
Repayment cadence
You can switch all your loans from monthly to fortnightly or weekly. The calculator models half the monthly repayment each fortnight, or a quarter each week. Either option produces the equivalent of 13 monthly repayments each year.
If a repayment does not cover interest
The calculator warns you when a debt’s current repayment is not enough to cover its estimated monthly interest. Without a change, that balance will rise rather than fall.
Contact your lender’s financial hardship team early if a higher repayment is not affordable. Lenders must consider financial hardship requests. You can also call the National Debt Helpline on 1800 007 007 for free, independent and confidential financial counselling.
Where the data comes from
The calculator loads your liabilities from the Net Wealth Tracker (/net-wealth). If you added a mortgage or loan using Quick Add, the rate, repayment amount, and term are pre-filled automatically. If a loan is missing its terms, the calculator shows an “Add loan terms ↗” link that opens the entity’s settings in a new tab.
Saving and revisiting scenarios
When you click Optimise my debt, the recommended result is saved with an optional default name such as “Boost by 500”. You can rename it or reopen it later from Saved scenarios.
What it does NOT model (yet)
- Lump-sum repayments (e.g. using a tax refund or bonus). Coming in a future update.
- HECS PAYG repayment bands (income-linked compulsory repayments). HECS is modelled as a straight-line paydown at 0% interest in v1.
- Tax, inflation, or fees — all projections are nominal and pre-tax.
Where it fits
The Debt Payoff Calculator lives under Tools → Modelling. You can also reach it from the “Debt-free date” button in the top-right of the Net Wealth Tracker page.
For the full picture — including how your assets grow alongside your liabilities — use the Net Wealth Forecaster.