GST calculator (Australia)
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GST formula (10%)
| Task | Formula | Example |
|---|---|---|
| Add GST | price x 1.1 | $100 becomes $110 |
| GST in an inclusive price | price / 11 | $110 / 11 = $10 |
| Price excluding GST | price / 1.1 | $110 / 1.1 = $100 |
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Frequently asked questions
How do I work out the GST in a price that includes GST?
Divide the GST-inclusive price by 11. A $110 price includes $10 GST, and the price excluding GST is $100.
How do I add GST to a price?
Multiply the GST-exclusive price by 1.1. $100 plus GST is $110.
Do I have to charge GST?
You must register for GST once your GST turnover reaches the registration threshold (check the current ATO threshold). If you are not registered, do not charge GST.