GST Calculator
Add or remove GST with the standard rates for Australia, New Zealand, Canada, India and Singapore built in.
Result
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Base (excl. GST) —
GST amount —
Total (incl. GST) —
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How it works
Add: total = amount × (1 + rate); remove: base = total ÷ (1 + rate)Frequently Asked Questions
How do I calculate GST in Australia?
Add 10%: multiply by 1.1. To find GST inside a total, divide by 11 — a $110 total contains $10 GST. That divide-by-11 shortcut works only for the 10% rate.
What are the GST rates by country?
Australia 10%, New Zealand 15%, Singapore 9%, Canada 5% federal (provinces add PST/HST up to ~15% combined), India uses slabs of 5%, 12%, 18% and 28% depending on the goods.
How do I remove GST from a price?
Divide by 1 plus the rate: an Indian invoice of ₹1,180 at 18% GST is ₹1,180 ÷ 1.18 = ₹1,000 base plus ₹180 GST. Subtracting 18% of the total gives the wrong answer.