Mortgage calculator.
A home. A plan.
A little more freedom.
Start with a home in mind. See what the repayments look like. Then discover how a little extra could bring mortgage-free closer.
NZD estimates. No sign-up needed. Your inputs stay on this page.
Estimated fortnightly repayment$1,571.58
The maths behind your plan.
This NZ mortgage repayment calculator estimates a fully repaying principal-and-interest loan. The loan is your home price minus your deposit. All amounts are in New Zealand dollars.
A smaller deposit increases the loan, repayments and interest. A 5% scenario does not confirm lending eligibility. Check the current Kāinga Ora First Home Loan requirements and any low-deposit fees or rate adjustments with your lender.
Calculation method and assumptions
For a loan P, periodic rate r and number of repayments n, the base repayment is P × r ÷ (1 − (1 + r)−n). At 0% interest it is P ÷ n.
We use 52 weekly, 26 fortnightly or 12 monthly periods per year. Each repayment first pays that period’s interest, then reduces the principal. Extra payments begin with the first repayment. The final repayment is capped at the remaining balance plus interest. Calculations keep full precision until values are displayed.
The annual rate stays constant throughout the entered term. This is an estimate using equal periods, not a lender’s dated daily-interest schedule. There are no fees, offset accounts, redraws, lump sums, interest-only periods or future rate changes. Time saved is rounded to the nearest month, and can include a smaller final payment.
For independent guidance, see Sorted’s mortgage calculator. Confirm your repayment amount, extra-payment limits and lending terms with your lender.
Mortgage calculator questions.
Can I use a 5% deposit?
You can model a 5% deposit, 20% or any other deposit size here. Kāinga Ora First Home Loans can support a 5% deposit for eligible buyers through participating lenders. Approval depends on the scheme and lender criteria. Low-deposit loans may have extra fees or a different interest rate; those costs are not automatically included in this calculator. Check the current requirements with Kāinga Ora and your lender.
How are mortgage repayments calculated?
This calculator uses the principal-and-interest annuity formula. Your annual interest rate is divided by 52 for weekly, 26 for fortnightly or 12 for monthly repayments. It assumes equal periods, payments at the end of each period and the same rate for the full term. Actual bank calculations can differ because of daily interest, payment dates, fees and rounding.
Does paying weekly or fortnightly save interest?
Each frequency here is calculated to repay the loan over the same term. A fortnightly amount is not simply half a monthly amount, and a weekly amount is not one quarter. Some lenders offer accelerated arrangements with more paid each year. To model paying more, add an extra payment and check the arrangement with your lender.
Can extra repayments pay off my mortgage sooner?
In this estimate, extra payments reduce the principal from the first repayment while your base repayment stays the same. This can shorten the loan and reduce interest. Your lender may restrict extra repayments on fixed-rate loans or charge fees, so check your loan terms.
Is the example interest rate a current mortgage offer?
No. The example rate is an editable assumption, not a live bank rate or a lending offer. Enter a rate quoted by your lender and try a higher rate to see how repayments could change. A fixed-rate period is usually shorter than the full mortgage term.
What other costs should I budget for?
Repayments exclude legal and valuation fees, lender charges, council rates, insurance, maintenance, body corporate or residents association fees, and any building or land costs outside your entered price. This calculator does not assess income, credit, affordability or lending eligibility.
Planning a new build? Read our new-build finance guide or explore Canterbury homes.
Estimates are general information, not personalised financial advice, lending approval or an offer of credit.