# Mortgage repayment calculator

> Your repayments by week, fortnight or month, and the interest you'll pay over the life of the loan.

Use it in a browser at https://buyingahouse.co.nz/tools/mortgage-repayments, or call it through the site's MCP server at https://buyingahouse.co.nz/mcp.

## 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.

## Common questions

### Is it cheaper to pay weekly, fortnightly or monthly?

Only slightly. On a $600,000 loan at 6.5% over 30 years, paying weekly saves about $900 in total interest compared with paying monthly, because your balance falls a little faster. Pick the schedule that matches your pay.

### What happens if interest rates go up?

On a $600,000 loan over 30 years, a rise from 6.5% to 7.5% adds about $186 to each fortnightly repayment. The line under your result shows what a 2 point rise does to your own numbers.

### How much can I borrow?

That depends on your income, your other debts, your living costs and your deposit. Banks also check you could afford the repayments at a test rate higher than the one they offer. A mortgage adviser can tell you how much each bank might lend you.