GST Calculator NZ

How the Three Rows Work

The NZ GST calculator keeps three prices on one card for a normal 15% supply. Inland Revenue’s GST guide IR375 treats GST exclusive as the price before GST, GST inclusive as the price that already includes GST, and the GST content as the tax itself. Type the one figure you have, then press the button on that row. The other two prices fill in.

Add GST

On Inland Revenue’s calculating your GST page, Hine sells headphones for $100 not including GST. The rate of GST is 15%, so $100 times 0.15 is $15. Adding $15 makes the total $115 including GST. Type 100 on the GST exclusive row and press Add GST. The plus GST calculator NZ total is the $115 the customer pays.

GST guide IR375 prints the same pair: product $100, GST $15, GST inclusive total $115. The GST exclusive calculator NZ starts from that $100. Press Add GST. That button is the add GST calculator NZ, which is the same job as an add GST NZ calculator. Those three figures can go on a tax invoice from the GST invoice generator.

GST on common amounts, worked examples

Some amounts come up again and again. Each line below is the 15% rate worked through the same three rows on the calculator above:

• $100 excluding GST → $15 GST → $115 including GST
• $200 excluding GST → $30 GST → $230 including GST
• $500 excluding GST → $75 GST → $575 including GST
• $1,000 excluding GST → $150 GST → $1,150 including GST

Going the other way, $1,150 including GST holds $150 of GST (1150 × 3 ÷ 23), leaving $1,000 before GST. Put any of these three-figure sets on a tax invoice from the GST invoice generator and the lines will reconcile.

GST in an Inclusive Price

Arthur, on the same Inland Revenue page, starts from the $115 total. He multiplies by 3, divides by 23, and gets $15 of GST. Taking $15 away from $115 leaves $100. That $100 is the price excluding GST. Type 115 on the GST inclusive calculator NZ row and press Get GST. Less GST on the less GST calculator NZ is that subtraction. The same $100 is the ex GST calculator NZ result, and the pre GST calculator NZ result.

IR375 prints a smaller case. An employee pays $100 cash toward a fringe benefit, and the GST on that $100 is $13.04. Taking 15% off the inclusive total uses the wrong base, because the GST is 3/23 of the price that already includes it. The excluding GST calculator NZ result is what remains after that GST comes out. Price the benefit itself on the FBT calculator. A page that only takes GST out of one inclusive price is the reverse GST calculator.

GST Content

If the GST line is the figure you already have, type it on the GST content row and press Get Prices. Inland Revenue’s headphones example starts from $15 of GST. Dividing that GST by 0.15 returns the $100 price before GST, and adding the two amounts returns the $115 total. The GST content, also called the GST component, is the tax line on its own. Use the GST content calculator NZ, which is the GST component calculator NZ, when that line is the figure you were given.

The NZ GST Calculator Formula

Inland Revenue’s formula for adding GST is the exclusive price times 0.15, which is the GST, then add that GST to the price. When the price already includes GST, IR375 says multiply by 3 and then divide by 23. For GST in NZ, this calculator uses the usual 15%. In 2026 this GST calculator NZ still follows that IR375 method, so the 2026 NZ GST calculator is the same sum. The GST NZ calculator steps are written out in GST maths NZ.

IR375 also describes dividing a GST inclusive price by 7.66666666 to get the GST component. It says you must keep at least 8 decimal places, because fewer places can give the wrong GST. The guide says multiplying by 3 and then dividing by 23 always gives an accurate answer. This NZ GST rate calculator uses that fraction and rounds each money line to the nearest cent. The GST rate NZ calculator on this page is 15% only. That fraction is the GST calculator NZ formula.

Is GST still 15% in New Zealand in 2026?

Yes. New Zealand's standard GST rate is still 15% for the 2026/27 tax year (1 April 2026 to 31 March 2027). Inland Revenue's GST guide IR375 describes GST as usually 15% on most goods and services, and this calculator uses the 15% rate only — the 3/23 fraction for taking GST out of an inclusive price works only at 15%.

If a bill looks different, the difference is usually zero-rated or exempt treatment rather than a rate change. The full GST guide sets out how the rate applies across registration, charging, and filing.

Sole Traders and the Self Employed

A GST registered sole trader charges GST the same way as any other registered business. IR375 describes GST as usually 15%, charged by GST registered businesses on most goods and services in New Zealand. A sole trader uses this GST calculator NZ on the same three rows, which is the GST calculator sole trader NZ. A self employed person who is registered uses the GST calculator NZ for the self employed the same way: plus GST on a quote, and Get GST when a supplier bill already includes the tax. Income tax on the profit is a different calculation, on the self employed tax calculator.

Whether you must register, or can register before you have to, sits on how to register for GST in NZ, the GST threshold guide, and should I register for GST voluntarily. Tradies use the same 15% sums, set out on GST for tradies NZ.

A Working Paper Before the GST Return

Inland Revenue says most people file their GST return in myIR, which does the calculations for you. This GST tax calculator NZ is a working paper for a price. It is not a GST return calculator NZ. A search for a GST calculator NZ IRD page, an NZ GST calculator IRD page, or an IRD GST calculator NZ page still ends in myIR for the return. This site follows IR375. It is not Inland Revenue. Save the PDF for your own file, then follow how to file your GST return in myIR.

There is no NZ GST calculator app to install. This free GST calculator NZ is an online GST calculator NZ: it runs in the browser on a phone or a computer, which makes it an NZ GST calculator online, and nothing is stored on our servers. Purchases you can claim are on claiming GST NZ. The details a supplier must show you are on taxable supply information.

Can I claim GST back? Is this a GST refund calculator?

This page is not a GST refund calculator. It works out the GST on one price; it does not calculate what you can claim back on a return.

A GST-registered business claims the GST it paid on business purchases and expenses through its GST return in myIR — the return does that calculation, not this page. Which purchases qualify is set out on claiming GST in NZ.

If you are a visitor leaving New Zealand and wondering about getting GST back at the airport, see the GST refund calculator for tourists.

When 15% Does Not Apply

IR375 describes GST as usually 15% on most goods and services in New Zealand, most goods imported into New Zealand, and some specified imported services. Do not run this NZ GST tax calculator on a price that is not charged at 15%. Exempt supplies and zero rated supplies are a different treatment, set out on exempt vs zero rated supplies.

GST charged at the border on a Customs value is not this 3/23 checkout sum. Use the import duty calculator for that. A wider map of the tax, from registration through filing, is the ultimate guide to GST in New Zealand.

Common Questions