Refinance Calculator Australia

Numbers stack up? Compare actual refinance offers next.

If the refinance still looks good after fees, term changes and feature trade-offs, it's time to compare real lenders — not just the first one with a cleaner rate card.

How this Refinance Calculator works

A refinance calculator compares your current loan against a proposed replacement using the details you enter for rate, balance, remaining term, repayment type and switching costs. It then estimates how your repayments, interest cost and overall position may change if you switch.

The question it really answers is not "is this rate lower?" but "is this new loan actually doing better work?" A refinance can lower repayments because the interest rate is sharper, because the term is longer, or because the structure has been tweaked in ways that look friendly now but cost more later.

The point of this tool is to make that behaviour visible. It separates three things that often get blurred together: monthly cash flow, total cost and loan structure. Only when all three improve (or at least don't get worse) does a refinance start to deserve serious attention.

This calculator is a guide, not a guarantee. It:

• Uses the rates, balances, terms, fees and cashback amounts you enter to estimate repayments, interest and savings.
• Treats switching costs and break costs as entered amounts and does not guess numbers you do not provide.
• Assumes rates stay at the levels you model unless you deliberately change them in a scenario.
• Does not include every lender fee, discount, package rule or future rate movement.

When refinancing may not help

Refinancing is not automatically clever just because the repayment looks smaller. These are the situations where the calculator earns its keep by saving you from a shiny but pointless exercise.

How to interpret your results

A refinance result should be read in layers, not like a jackpot screen.

• Repayment layer. Are repayments lower, and by how much? Does that relief actually matter to your budget?
• Cost layer. After switching costs and fees, is total interest meaningfully lower or only marginally different?
• Structure layer. Did the new loan improve features, term and flexibility, or just create a prettier statement?

If the new loan wins on repayment but loses on total interest because the term stretches out, that is a partial win at best. If the savings are tiny and the hassle and risk are large, it is a dressed-up sideways move. The refinance that matters is the one that improves your position in real life — not just in lender marketing.

A sharper way to refinance

Refinancing is often sold as a way to "save money," but most people are really chasing more breathing room. That's fine — just make sure the breathing room isn't borrowed from your future self.

• Enter your current balance, rate and remaining term.
• Enter the new loan rate and test both a matched remaining term and a longer reset term.
• Compare the monthly repayment difference and check how that feels against your budget.
• Add discharge fees, application costs, valuation costs and any break costs.
• Check the break-even point — when savings overtake the cost of switching.
• If the new repayment is lower, test whether keeping repayments near the old level pays the new loan off faster.
• Then compare refinance loans with the right features and structure, not just the lowest teaser rate.

The impulsive version of you says "new rate lower, done." The wiser version says "show me the cost after friction, the term impact and whether this move still looks smart after a bad month." LoanGorilla listens to the second one.

Calculator assumptions

This calculator estimates current and new loan repayments using the standard amortisation (annuity) formula on a monthly basis. Interest-only repayments cover interest only — the principal isn't reduced during that phase, and the post-IO repayment is calculated on the remaining balance over the remaining term. Switching costs (discharge, application, valuation, break costs) and any cashback are summed to a net switching cost figure. The break-even period assumes the monthly repayment saving is held constant. Rate changes after settlement, package fees, ongoing service fees, redraw rules, lender-specific discounts and other product-level details are not modelled. The calculator does not constitute financial advice. Reviewed by the LoanGorilla editorial team — last updated May 2026.