Fixed vs Floating Mortgage Calculator NZ
This calculator compares a fixed mortgage rate against a floating rate on a New Zealand home loan, showing exactly what the flexibility of floating costs you in dollar terms. Enter your loan amount, the fixed rate on offer, the floating rate on offer, and your loan term in years, and the tool works out the standard table repayment at each rate. You get back the fixed repayment, the floating repayment, the extra amount you pay each month on the floating rate, and the extra interest that adds up to over a year. Floating rates run higher than fixed because you are paying for the ability to make extra repayments, change your repayment amount, or refinance at any time without a break fee, while fixing locks in a lower rate but commits you to it for the term. Use the calculator to see whether that flexibility is worth the extra cost for your situation, or to compare offers from different lenders before you fix. Many borrowers split their loan between fixed and floating to get some certainty and some flexibility rather than choosing one or the other outright. The figures are based on standard table loan repayments and do not capture the value of making lump-sum repayments or the cost of breaking a fixed rate early, so treat the result as an indicative comparison rather than a loan offer.
Compares table repayments at each rate over the term. The flexibility of floating (extra repayments, no break fees) has real value not captured here. Many borrowers split the loan between fixed and floating. Estimate only, not a loan offer.
How it works
The calculator works out the standard table repayment for your loan at both the fixed and floating rates over the term, using the amortisation formula. The difference is what floating costs you each month and year in extra interest. That is the price of the flexibility floating gives, which you can weigh against the certainty and lower cost of fixing, or split the loan to get some of each.
Worked example
On a $600,000 loan over 30 years, a 5.79% fixed repayment is about $3,516 a month, while a 6.69% floating repayment is about $3,866, around $350 a month more, or roughly $4,200 a year, for the flexibility floating provides.
Related calculators
- Mortgage Repayment Calculator: repayments.
- Fixed-Rate Rollover Calculator: when a fix ends.
- Mortgage Break Fee Calculator: break fees.
- Revolving Credit Calculator: flexible facilities.
- Fixed vs Floating Mortgage: background on this topic.
- Breaking a Fixed Mortgage Guide: background on this topic.