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Australian GST calculator
Add 10% GST to a price, or work out the GST already inside one. The inclusive answer is the one people get wrong — it is a division by 11, not by 10.
$
Price excluding GST$100.00
GST (10%)$10.00
Price including GST$110.00
$100.00 × 10% = $10.00 GST
Australian GST is 10%. To find the GST inside a price that already includes it, divide by 11 — not by 10. Dividing by 10 overstates it, which is the most common mistake on a tax invoice.
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