Mortgage calculator

This is a powerful mortgage calculator, although if you are new to on-line calculators you may wish to start with something a bit more basic. Try here» On some browsers, this full page may take a moment to load. We also recommend you turn off any pop-up blocker before using this page.

There are two identical calculators here, allowing you to compare one scenario with another.

READ THIS FIRST. Start with deciding what you want to know, and clicking the corresponding 'radio button' ¤ – this tells the calculator what answer you are looking for, and the result is displayed in the box next to that button. You can only solve for one attribute at a time.

Option One
Option Two
amount ($)
rate(% p.a.)


Interest + fees paid :
Principal repaid :
Total amount paid :
Interest + fees paid :
Principal repaid :
Total amount paid :

click on a rate to select it

Institution Variable 6 mths 12 mths 18 mths 24 mths 36 mths 48 mths 60 mths
ANZ 5.79* 4.99* 4.45* 4.85* 4.79* 4.99* 5.55* 5.69*
ASB 5.80 5.25 4.45 4.69 4.69 4.89 5.35 5.49
BNZ 5.90 4.99 4.69 4.79 4.79 4.99 5.19 5.39
Co-operative Bank 5.75* 4.50* 4.10* 4.29* 4.35* 4.49* 4.99* 5.19*
HSBC 5.89 4.85 3.99 4.19 4.69 4.99 5.29
Kiwibank 5.80* 4.99* 4.55* 4.79* 4.99* 4.99* 5.09*
SBS Bank 5.89* 5.25* 4.85* 5.15* 5.05* 5.49* 5.89* 6.09*
TSB Bank 5.80* 5.35* 4.45* 4.69* 4.69* 4.99* 5.45* 5.49*
Westpac 5.95 4.99 4.69 4.79 4.79 5.19 5.29 5.49


How can i calculate the following?

i paid interest only for the last 3 years , say for the sake of this question it was 100,000

and i have a debt " mortgage" of 400,000 and now i am switching into  principal+interest, how can i claculate my repayments, or is this option not possible with the above calculators?

Thank you

You can make this calculator work for 'interest only' by setting the Balloon payment to the same amount as the original Loan amount.

If you are switching from an interest-only version to P+I, then this calculator should work just fine. The interest-only period becomes irrelevant, as you paid down no principal over this time. Just set your starting principal to the Loan amount ($400,000 ?), and choose your Term and Interest rate.

Try it gives a better picture

Hi there,

Can you please show me how you calculate Straight line repayment? Say, principal is $132K, interest is 6.2%, monthly payment is $1200. How many years will it take me to pay off the mortgage?

Thank you

Select Loan Term as the radio box

Now put in principal amount, Interest rate, and repayment amount.

I'm getting 13.65 years.

Hi there, just wondering if you have an iPad app for all your calculators - would be really handy.... Thanks and really love the tools you've made available for users.

Thanks all.

Small niggle.  Why does your mortgage calculator calculates terms as ie "12.21" years.  What does that mean in months and weeks.  Is it a % of 12 months or is 12 years 2 months & 1 week.  Why not calculate in years and weeks? Thanks.

This is a great calculator, I'm going to save thousands!

Hi. This is a really good calculator. Can you add a "save as a PDF file" option please. Thanks

Hi, there's a problem with this calculator now. If I want to find out the loan term by clicking on that button, then try to enter a repayment amount, it glitches out and bounces back to another amount. There is a work around but it means deleting a single digit then entering a new one and working along to replace all digits.
One other thing that hasn't been answered from 2012 is : What does 12.21 years mean? It seems to be 12 and point 21 years which is nearly 12 years, 11 weeks. Thanks