MORTGAGE CALCULATOR
What will the bank really charge you? Payments, and the lifetime interest bill.
Where each year's payments go
| Year | Interest paid | Principal paid | Still owing |
|---|
How to use this calculator
Enter your loan amount, interest rate, and mortgage length, and this calculator will work out your repayments — and the total interest you'll hand the bank over the life of the loan.
Switch the payment frequency to see weekly or fortnightly repayments. The chart shows how each year's payments split between interest and actually paying down the loan — in the early years, most of your money is going to the bank.
A worked example
Say you borrow $640,000 over 30 years at 5.5%.
Punch that in and your repayment lands around $3,634 a month. Feels manageable enough. But here's the number nobody wants to look at: over the full 30 years you'll pay back roughly $1.3 million. That's about $668,000 in interest - you basically buy the house twice.
That's not a reason to panic. It's a reason to understand the two levers that move that interest number hard: your rate, and how fast you pay it off.
Put your loan amount, rate and term in above and see the real total, not just the monthly.
What most people get wrong about their mortgage
People fixate on the monthly repayment and ignore the total interest. That's backwards, because the total is where the life-changing money is.
Two small moves do enormous work. Knock your rate down by even half a percent and you save tens of thousands over the life of the loan. And chip in extra repayments early - when almost all your payment is interest - and you carve years off the mortgage and save a fortune, because every extra dollar goes straight at the principal.
An extra $200 a month on that $640,000 loan can take years off the term and save well over $100,000 in interest. Same house, same rate, just refusing to drag it out. The bank's happy for you to take the full 30 years. You shouldn't be.
This calculator and page are general information only and not financial advice. Everyone's circumstances will vary - always do your own research and consult your own financial professionals before making decisions.