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GST calculator NZ

Add GST to a price, or work out how much GST is inside a price that already includes it.

It uses the New Zealand GST rate of 15%, the rate registered businesses charge on most goods and services.

How it's calculated

To add GST, multiply the price by 15% and add the result to the price.
To take GST out of an inclusive price, multiply it by 3 and divide by 23. That's the same as 15 divided by 115.

An example

A quote of $1,000 including GST has $130.43 of GST in it. The price before GST is $869.57.

Frequently asked questions

Why is the GST fraction 3/23?

An inclusive price is 115% of the price before GST. The GST part is 15/115 of it, which simplifies to 3/23.

Who has to charge GST?

Businesses registered for GST charge it on most taxable supplies they make. Inland Revenue explains when you need to register.

Is GST charged on everything?

No. Some supplies are exempt or zero-rated. Check Inland Revenue's GST pages for what applies to your goods or services.

Key terms

GST: Goods and services tax, a tax on most goods and services sold in New Zealand.
GST-inclusive: A price that already has GST added.

The same calculation in other countries

Up-to-date official data

Data checked against the official source on 14 October 2026.

We check the official sources automatically, every day.

Inland RevenueCharging GST

See all sources

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