How to calculate GST
GST in a GST-inclusive price: price ÷ 11
Price before GST: price ÷ 1.1
A common mistake is taking 10% off a GST-inclusive price. That gives too low a figure: the GST inside $110 is $10, which is one eleventh, not 10%.
Examples
| Price excl. GST | GST | Price incl. GST |
|---|---|---|
| $100.00 | $10.00 | $110.00 |
| $250.00 | $25.00 | $275.00 |
| $909.09 | $90.91 | $1,000.00 |
| $4,545.45 | $454.55 | $5,000.00 |
What GST applies to
GST is a 10% tax on most goods and services sold in Australia. Some things are GST-free, including most basic food, many medical and health services, and most education courses. Businesses must register for GST once their turnover reaches $75,000 a year ($150,000 for non-profits). Check the ATO for your situation.
Need other percentages? Use the percentage calculator.
Frequently asked questions
How do I work out GST from a total?
Divide the GST-inclusive total by 11. The GST in $1,100 is $100.
How do I add GST to a price?
Multiply by 1.1. $250 plus GST is $275.
What is the GST rate in Australia?
10%, on most goods and services.
When do I need to register for GST?
When your business turnover is $75,000 or more a year, or $150,000 for a non-profit. Taxi and ride-sourcing drivers must register regardless of turnover.
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Last updated October 2026.