Free GST Calculator for New Zealanders
NZ GST is 15%. The calculator works in either direction: enter a GST-exclusive amount to add GST, or a GST-inclusive amount to find the GST and net component.
Your amount
Adding 15% GST to $1,000.
About our GST Calculator
Adding GSTGSTGoods and Services Tax; flat 15% consumption tax on most NZ goods and services.View in glossary → is multiplying by 1.15. Removing GST is dividing by 1.15. NZ GST has been a flat 15% since 1 October 2010, applied to almost every supply made by a registered business, with a small set of zero-rated and exempt categories outside that.
The calculator handles both directions. Switch the toggle to "Add GST" and enter a net figure to see the GST and the inclusive total. Switch to "Remove GST" and enter an inclusive figure to see the net and the GST component. The GST rate is locked at 15% because that is the NZ rate; the field accepts other rates only for cross-jurisdiction comparisons.
For freelancers, tradies, and small businesses, the page is most useful for invoice maths, expense reconciliation, and the quick check on whether a supplier’s tax invoice is showing the right numbers.
How to use it
Choose Add or Remove. Type the amount. The result panel shows the net figure, the GST component, and the inclusive total in one view.
For invoice maths, set the toggle to Add and enter your quoted price excluding GST. The inclusive total is what the customer pays.
For expense reconciliation, set the toggle to Remove and enter the inclusive total off the supplier’s receipt. The GST component is what you can claim as an input on your next return.
Why use it
The most common GST mistake on small-business invoices is treating a GST-inclusive price as if it were GST-exclusive (or vice versa). A $4,600 GST-inclusive price quoted as "plus GST" inflates the bill by another $690 in error. A $4,000 + GST price entered into accounting software as $4,000 inclusive understates revenue by $522 and short-pays the IRD.
The calculator runs the maths the same way IRD-approved accounting software does. Two of the three figures (net, GST, inclusive) flow from one given input, so a mismatch on any one of them shows up immediately when you punch in the others.
For voluntary-registration decisions, the calculator also makes the trade-off concrete. Charging 15% on top of every sale costs the customer 15% if they are not GST-registered themselves. The recoverable input GST on business expenses can offset some of that, but only some.
The maths behind it
Inclusive = Net × 1.15 | Net = Inclusive ÷ 1.15 | GST = Inclusive × 3 ÷ 23 Adding GST scales the net figure by 1.15. Removing GST divides the inclusive figure by 1.15. The handy short-cut for the GST component of an inclusive total is to multiply by 3 and divide by 23: $115 inclusive becomes $115 × 3 ÷ 23 = $15 GST. The maths only works because the rate is exactly 15%; if the GST rate ever changed, the 3/23 short-cut would change with it.
Worked example
Chloe, freelance copywriter in Palmerston North, working out invoice totals.
Chloe quotes a client $4,000 for a project. She is GST-registered, so she invoices $4,000 + GST: $4,000 × 1.15 = $4,600 total. The $600 GST sits in a separate ledger account until her next return.
Her phone bill that month arrives at $230 GST-inclusive. To work out the GST claimable as an input, she divides by 1.15: $230 ÷ 1.15 = $200 net, leaving $30 of input GST she can offset.
On her next bi-monthly GST return, the $600 collected from the client minus the $30 (and any other input GST from business expenses) is the net amount Chloe pays to Inland Revenue.
If a quarter of her year’s expenses are GST-bearing, her annual GST liability lands at roughly 15% of revenue minus 15% of those expenses.
Things to keep in mind
- $60,000 registration threshold. Registration is compulsory once your turnover is, or is expected to be, at least $60,000 in any 12-month rolling period. Below that, you can register voluntarily; above it, you must.
- Zero-rated supplies. Some supplies carry a 0% GST rate rather than the standard 15%. Exports, sales of going-concern businesses to other GST-registered buyers, and certain financial services are zero-rated. The GST is collected at 0%, which still lets the seller claim input GST on costs.
- Exempt supplies. Residential rents, financial services, and donated goods sold by a non-profit are GST-exempt. Exempt is different from zero-rated: no GST is collected, and the seller cannot claim back any GST on related costs.
- Filing frequency. GST-registered businesses file monthly, bi-monthly, or six-monthly depending on turnover. Most small NZ businesses are on the bi-monthly cycle; the six-monthly option is available below $500,000 turnover, monthly is required above $24 million.
- Second-hand goods. A registered business buying second-hand goods from a non-registered seller can claim a notional input credit (the GST equivalent imputed into the purchase price), even though no GST was charged on the sale.
NZ-specific notes
FAQs
How do I find the GST in a GST-inclusive price?
Multiply by 3 and divide by 23. A $115 GST-inclusive price contains $15 of GST and $100 of net. Equivalently, divide the inclusive total by 1.15 to get the net, then subtract the net from the inclusive total to get the GST.
When do I have to register for GST?
Once your turnover is, or you expect it to be, at least $60,000 in any 12-month rolling period. The 12 months can look forward or back; it does not have to align with the tax year. Voluntary registration is available below $60,000 if it makes commercial sense to recover input GST.
Can I claim GST back on business purchases?
Yes, on purchases that relate to making taxable supplies, once you are GST-registered. The receipt or tax invoice has to show the supplier’s GST number and meet the IRD invoice-content rules. Personal-use purchases and exempt-supply costs are not claimable.
What is the difference between zero-rated and exempt?
Zero-rated supplies (exports, going-concern sales, certain financial supplies) are taxed at 0%, but the seller can still claim input GST on costs. Exempt supplies (residential rent, financial services) carry no GST at all, and the seller cannot claim input GST.
Do I charge GST to overseas customers?
Generally not. Goods physically exported and certain services supplied to non-residents outside NZ are zero-rated. The export documentation (shipping records, customs entry) is what supports the zero-rating in an audit.
How often do I file a GST return?
Monthly is required above $24 million annual turnover. Six-monthly is available below $500,000 turnover. Bi-monthly is the default for everyone in between, and is the most common for small NZ businesses. The cycle is fixed when you register and reviewed annually.
What if I deregister?
Cancellation triggers a "change of use" adjustment: any business assets you keep for personal use are treated as a deemed sale at market value, with GST output owed on that value. The same applies to long-life assets like vehicles, plant, and stock-in-hand.
References & sources
- Inland Revenue, "Working with GST (IR375)". ird.govt.nz
- Inland Revenue, "Registering for GST". ird.govt.nz
- Inland Revenue, "GST overview". ird.govt.nz
- Inland Revenue, "GST on low-value imported goods". ird.govt.nz