Mortgage Repayments Calculator
Work out periodic repayments, total interest and total cost for any loan amount, rate and term.
Repayment (monthly)
$5,206
≈ $5,206 / month
Amortisation summary (yearly)
| Year | Principal | Interest | Balance |
|---|---|---|---|
| 1 | $10,054 | $52,417 | $839,946 |
| 2 | $10,696 | $51,776 | $829,250 |
| 3 | $11,378 | $51,094 | $817,872 |
| 4 | $12,104 | $50,368 | $805,768 |
| 5 | $12,876 | $49,596 | $792,892 |
| 6 | $13,697 | $48,774 | $779,194 |
| 7 | $14,571 | $47,901 | $764,623 |
| 8 | $15,501 | $46,971 | $749,123 |
| 9 | $16,490 | $45,982 | $732,633 |
| 10 | $17,542 | $44,930 | $715,091 |
Showing first 10 years of 30.
About this calculator
This free mortgage repayments calculator estimates the periodic repayment, total interest paid and total cost of any Australian home loan. It supports principal-and-interest (P&I), interest-only and split structures, and lets you switch between weekly, fortnightly and monthly schedules so you can see exactly how much you’ll be paying after settlement.
How the numbers are worked out
For a standard P&I loan, the calculator uses the annuity formula every Australian lender uses: it takes your annual rate, divides it down to the period you’ve picked, and solves for the level repayment that fully amortises the balance over the remaining term. Interest-only loans are handled separately — during the interest-only window you only service the interest, then the calculator switches to P&I on the residual balance for the rest of the term.
Assumptions and limitations
- The interest rate is held constant for the full term — rate rises and cuts are not modelled.
- No fees: establishment, monthly service, discharge and LMI are excluded.
- No offset or redraw — subtract your expected offset balance from the loan amount to approximate the effect.
- Repayments are assumed to start at settlement and continue uninterrupted.
When to use it
Use this calculator when you’re shortlisting properties, comparing fixed vs variable rates, deciding between a 25 and 30-year term, or stress-testing your budget against a 1–2% rate rise. For a full serviceability picture (how much a bank will actually lend you), use our Borrowing Capacity calculator instead, which applies APRA’s 3% buffer and standard living-expense benchmarks.
Frequently asked questions
- How are mortgage repayments calculated in Australia?
- Principal-and-interest repayments use the standard annuity formula: M = P × r / (1 − (1 + r)^−n), where P is the loan balance, r is the periodic interest rate (annual rate divided by 12 for monthly, 26 for fortnightly, 52 for weekly) and n is the total number of repayments. Interest-only repayments are simply P × r for the interest-only period, then revert to P&I over the remaining term.
- Are fortnightly repayments really cheaper than monthly?
- Yes — but only if your lender treats them as a true fortnightly schedule rather than "monthly ÷ 2". Because there are 26 fortnights in a year (not 24), paying fortnightly means you make the equivalent of 13 monthly payments per year, which can shave several years off a 30-year loan. This calculator uses true fortnightly and weekly periods.
- Does this calculator include LMI, stamp duty or fees?
- No. It calculates the repayment on the loan amount you enter. Lenders Mortgage Insurance is typically capitalised onto the loan, so add it to the loan amount if your deposit is under 20%. Use our Stamp Duty calculator for state transfer duty and government fees.
- What interest rate should I use?
- Use the actual rate your lender has quoted. For "what-if" planning, use the current owner-occupier P&I variable rate plus a 1–2% buffer to stress-test against future rate rises. APRA requires lenders to assess serviceability at the contract rate plus a 3% buffer.
- Can I model an offset account?
- Indirectly — reduce the loan amount by the average balance you expect to hold in your offset. Money in offset behaves like an extra repayment for interest-calculation purposes, but you keep access to the cash.
Estimates are indicative only and intended as a starting point. Actual figures depend on lender policy, market conditions, professional fees, taxes and other costs. Always confirm with a licensed broker, accountant, valuer or solicitor before acting.