New Zealand GST Calculator
Use this quick tool to add 15% GST to a GST-exclusive amount, or remove GST from a GST-inclusive total.
If you need a fast and reliable GST calculator for New Zealand, this page gives you both: a practical calculator and a clear explanation of how Goods and Services Tax works in everyday situations.
How GST works in New Zealand
In New Zealand, the standard GST rate is 15%. GST applies to most goods and services sold by GST-registered businesses. Whether you are a freelancer, contractor, retailer, consultant, or small business owner, you will often need to switch between:
- GST exclusive prices (before GST is added), and
- GST inclusive prices (after GST is included).
This is why a New Zealand GST calculator is useful for quotes, invoices, bookkeeping, and pricing decisions.
How to use this GST calculator
1) Enter your amount
Type the amount in NZD. You can enter whole numbers or decimals, for example: 500 or 500.75.
2) Choose calculation type
- Add GST: Use when your amount is GST exclusive and you want the final total.
- Remove GST: Use when your amount is GST inclusive and you want to extract the GST portion.
3) Keep the GST rate at 15%
The calculator defaults to 15%, which is the standard New Zealand GST rate.
4) Click calculate
You will see the GST amount, the GST-exclusive amount, and the GST-inclusive amount in NZD.
GST formulas (New Zealand)
Here are the formulas used behind the scenes:
- Add GST: GST = Amount × 0.15; Total = Amount + GST
- Remove GST: Exclusive = Inclusive ÷ 1.15; GST = Inclusive − Exclusive
These are the same formulas many accounting tools and invoice systems use.
Examples
Example A: Adding GST
You quote a client $1,000 plus GST.
- GST = $1,000 × 15% = $150
- Total incl GST = $1,150
Example B: Removing GST
You received a payment of $230 including GST.
- GST exclusive amount = $230 ÷ 1.15 = $200
- GST portion = $30
When people commonly use an NZ GST calculator
- Creating quotes and proposals
- Sending invoices to clients
- Checking supplier bills
- Reconciling transactions in accounting software
- Preparing GST returns and reviewing sales totals
Common mistakes to avoid
- Using 15% incorrectly when removing GST (you divide by 1.15, not subtract 15%).
- Mixing inclusive and exclusive prices in one quote without clear labels.
- Manual rounding errors across multiple line items.
- Assuming every transaction has GST when some may be zero-rated or exempt.
Quick FAQ
What is the current GST rate in New Zealand?
The standard GST rate is 15%.
How do I calculate GST on a price?
Multiply the GST-exclusive price by 0.15 to get GST, then add it to the original amount.
How do I remove GST from an inclusive amount?
Divide the GST-inclusive amount by 1.15 to get the GST-exclusive amount. The difference is GST.
Is this tool a substitute for professional tax advice?
No. This calculator is for general guidance and quick checks. For tax compliance matters, use official IRD guidance or speak with a qualified accountant.
Final thoughts
A simple GST calculator can save time and prevent costly errors. Use it before sending invoices, reviewing bills, or preparing reports so your numbers are accurate and consistent. If you work with GST regularly in New Zealand, this one habit can improve both your confidence and your cash flow visibility.