Free calculator
GST Calculator
Add GST to a price or find the GST inside one. Australia at 10%, New Zealand at 15%, every Canadian province, Singapore and India.
Including tax
A$110.00
- Excluding tax
- A$100.00
- Tax at 10%
- A$10.00
- Including tax
- A$110.00
A worked example
An Australian invoice for A$1,100 including GST. Australian GST is 10%, so the GST portion is exactly one eleventh of the total — a shortcut the ATO itself publishes.
| Total including GST | A$1,100.00 |
|---|---|
| Price excluding GST | A$1,000.00 |
| GST at 10% | A$100.00 |
The one-eleventh shortcut only works at 10%. At New Zealand's 15% the GST portion is three twenty-thirds, which is why it is easier to let the calculator divide.
Common questions
- How much is GST in Australia?
- 10% on most goods and services. Basic food, most medical care and education are GST-free, and exports generally are too.
- How do I calculate GST backwards?
- Divide the GST-inclusive total by 1.1 in Australia, or by 1.15 in New Zealand. At Australia's 10% you can also just divide the total by 11 to get the GST itself.
- Why does Canada have so many rates?
- Because provinces tax separately. Some harmonise theirs with the federal 5% into a single HST — Ontario at 13%, the Atlantic provinces at 15% — while others stack a provincial sales tax on top, and Alberta adds nothing at all.
- Do I need to register for GST?
- It depends on turnover. In Australia registration is required once turnover reaches A$75,000 a year, or A$150,000 for non-profits; other countries set their own threshold. Check with the local tax authority.