Mortgage calculator
Work out your mortgage repayments each week, fortnight or month, and the interest you'll pay over the whole term.
Fortnightly repayment
$1,551.29
| Total interest over 30 years | $580,007 |
| Total repaid | $1,210,007 |
If the rate rises 2 points to 6.95%, the fortnightly repayment becomes $1,923.85, which is $372.56 more.
Would a lower rate help bring down your fortnightly repayment of $1,551.29?
A licensed mortgage adviser will look at your situation and tell you which rates and loan options you might qualify for. This advice is free.
How this calculator works
The calculator works the way banks do for a table loan. Every repayment is the same, and as time goes on, more of each one goes to the principal and less to interest. The calculator splits the annual rate across the repayments in a year, then works out the repayment that pays off the loan by the end of the term.
The result covers principal and interest only, without fees, insurance or rate changes. Most New Zealand home loans are fixed for 1 to 5 years and then refixed, so treat the total interest as an estimate at today's rate.
The calculator starts with a $630,000 loan, which is about the national median sale price of $784,363 minus a 20% deposit, at 4.95%, the average 1-year special rate at the end of October 2026. You can change these to match your own loan.