Free tool
GST calculator
Add or remove GST for New Zealand and Australia in a click. Free, instant and accurate.
How to use this GST calculator
Enter an amount and choose your rate, 15 percent for New Zealand or 10 percent for Australia. Pick Add GST to work out the GST to add to a price before GST, or Remove GST to pull the GST out of a GST-inclusive total. The three figures update as you type.
How GST is calculated
To add GST, multiply the amount by the rate. On a $100 sale in New Zealand, GST is 100 times 0.15, which is $15, for a total of $115. To remove GST from a total, divide by 1 plus the rate. From a $115 total, the amount before GST is 115 divided by 1.15, which is $100, so the GST portion is $15.
When you need to charge GST
In New Zealand you must register for GST once your turnover passes $60,000 in a 12-month period. In Australia the GST registration threshold is $75,000. Once registered, you add GST to your prices, claim GST back on your purchases, and file the difference. Our GST return guide and BAS guide walk through the detail.
Tip: doing this by hand for every invoice adds up. Countova applies the right GST to every sale and purchase automatically and prepares your return as you trade, so you are not reaching for a calculator at the end of the period. Rates and thresholds can change, so confirm current figures with Inland Revenue or the ATO.
Stop calculating, start automating
Countova works out GST, margins and more on every transaction automatically, with NZ GST and Australian BAS built in. Start free for 14 days.
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