GST Calculator Australia: Add GST, Remove GST and Avoid Pricing Mistakes
Learn how GST works in Australia, how to add GST, how to remove GST and when to use a GST calculator for invoices, pricing and quotes.
GST in Australia is charged at 10% on most goods and services. The confusing part is not the rate itself. It is knowing whether a number already includes GST or whether GST still needs to be added.
How to add GST
To add GST to a GST-exclusive amount, multiply by 1.1. For example, $100 before GST becomes $110 including GST.
How to remove GST
To remove GST from a GST-inclusive total, divide by 1.1. For example, $110 including GST becomes $100 before GST and $10 GST.
When to use a GST calculator
Use a GST calculator when preparing invoices, checking supplier costs, building ecommerce pricing, quoting jobs or separating GST for bookkeeping.
Common GST mistake
Do not subtract 10% from a GST-inclusive price to remove GST. That gives the wrong pre-GST amount. Divide by 1.1 instead.