Work out repayments on any home loan in seconds — principal & interest or interest-only, weekly, fortnightly or monthly. Built for Australian brokers to run live with clients.
Your loan
Your repayment
How brokers use this
- Run it live in the meeting. Drag the rate and loan sliders while the client watches — seeing the repayment move is far more powerful than quoting a number.
- Sell the fortnightly trick. Switch frequency to fortnightly: because there are 26 fortnights (not 24), clients make the equivalent of an extra month’s repayment a year and cut years off the loan. A great, no-cost value-add.
- Frame interest-only honestly. Toggle IO to show the lower repayment, then P&I to show the true cost — a clean way to demonstrate Best Interest Duty reasoning in the conversation.
- Stress-test it. Nudge the rate up 1–2% to show what a client could handle before they commit. Reassuring for them, and good file evidence for you.
How the repayment calculator works
The calculator uses the standard amortisation formula to work out a level repayment that pays your loan to zero over the term. For a principal-and-interest loan, each repayment covers the interest charged for the period plus a slice of the principal; early on, most of the payment is interest, and over time the balance tips toward principal.
For an interest-only loan, the repayment covers only the interest, so the balance doesn’t reduce — repayments are lower, but you pay more interest over the life of the loan and face a step-up when the IO period ends. The calculator recomputes instantly as you change the loan amount, interest rate, term, repayment type and frequency, so you can compare scenarios side by side.
Fortnightly and weekly figures are calculated on the true number of periods in a year (26 and 52), which is why paying fortnightly typically clears the loan faster than paying monthly.
Frequently asked questions
What’s the difference between principal & interest and interest-only?
Principal & interest (P&I) repayments reduce the loan balance over time, so the debt is cleared by the end of the term. Interest-only (IO) repayments cover only the interest for a set period, so the balance stays the same — repayments are lower during the IO period but higher afterwards, and you pay more interest overall. IO is often used by investors; owner-occupiers usually pay P&I.
Do fortnightly repayments really save money?
Yes, if they’re set as half the monthly amount. There are 26 fortnights in a year, which equals 13 monthly payments rather than 12 — so you make roughly one extra month’s repayment a year without noticing, cutting years of interest off a typical loan. This calculator shows the effect when you switch frequency.
Is this repayment a formal quote?
No. It’s an estimate to help with planning and conversations. Actual repayments depend on the lender’s rate, fees, offset arrangements and how they calculate interest. Always confirm exact figures with the lender or your mortgage broker before making decisions.
How can I lower my repayments?
Options include securing a lower interest rate (a broker can review this for you), extending the loan term, switching to interest-only for a period, or using an offset account to reduce the interest charged. Each has trade-offs — a broker can weigh them against your goals under Best Interest Duty.
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Disclaimer: This calculator provides estimates for general information only and is not credit assistance, a credit quote, or financial advice. Results do not account for all fees, charges or lender-specific interest calculation methods. Figures should be confirmed with the relevant lender or a licensed mortgage broker. Consider your obligations under the National Consumer Credit Protection Act 2009 and Best Interest Duty.