How to use this tool
- Enter your own confirmed figures or use the labelled fictional example.
- Calculate, compare the breakdown and check the assumptions below.
- Copy or download the result, or print it for your own records.
How the calculation works
A 100% offset reduces the balance charged monthly interest, capped at the outstanding loan. The same loan repayment is used in both paths. The offset loan can have an entered rate premium, and extra annual fees are spread monthly until that loan is repaid.
Useful limits to know
The entered offset balance stays constant and separate from principal repayments. There are no deposits, withdrawals, changing rates, lender daily-interest calculations, tax effects or interest earned on the offset cash. The comparison is limited to interest and entered extra fees; it does not assess a lender or product.
Common questions
Is it free?
Yes. There is no account, subscription or payment form for this tool.
Are the example rates current offers?
No. Examples are fictional scenarios, not quoted products or forecasts. Enter confirmed figures and review the assumptions before relying on a result.
Does it connect to my bank or investment account?
No bank or investment account is connected. This is an illustrative browser calculation.
Sources and credits
Implementation and source links checked 26 October 2026. This is an independent tool; the sources do not endorse Elaris.
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