GST Calculator Australia – Add or Remove 10% GST
Work out the GST on an Australian taxable sale. Add 10% GST to a GST-exclusive amount, or take GST out of a GST-inclusive amount using the official divide-by-11 method. The rate used is the ATO’s published 10% goods and services tax.
How Australian GST is calculated
GST is 10% of the GST-exclusive price of a taxable sale. If you already have the GST-inclusive price, the GST inside that price is one-eleventh of it. The ATO states that the GST rate is 10%, meaning GST is 1/11th of the amount charged, and the Business Activity Statement worksheet divides taxable GST-inclusive sales by 11.
A common error is to take 10% of a GST-inclusive total. That overstates the GST. A $110 inclusive price contains $10 of GST, not $11. This calculator uses divide-by-11 when you choose “remove GST”.
- Add GST: exclusive amount × 10% = GST; exclusive + GST = inclusive.
- Remove GST: inclusive amount ÷ 11 = GST; inclusive − GST = exclusive.
What this calculator does not cover
Some supplies are GST-free or input-taxed. Luxury car tax, wine equalisation tax, imported goods customs duty, and the $75,000 GST registration threshold are separate ATO topics. Use this page only for a standard 10% taxable supply. Confirm the treatment of a sale on the ATO site before you report it.
Frequently Asked Questions
What is the GST rate in Australia?
The goods and services tax (GST) is a broad-based tax of 10% on most goods, services and other items sold or consumed in Australia. The Australian Taxation Office publishes this rate. Some supplies are GST-free or input-taxed and do not use this 10% calculation.
How do I add 10% GST to a price?
Start with the GST-exclusive amount and multiply by 10% (or multiply by 1.1 for the GST-inclusive total). A $1,000 exclusive price has $100 of GST and a $1,100 inclusive price. This calculator rounds each money figure to the nearest cent.
How do I remove GST from a GST-inclusive amount?
Do not take 10% of the inclusive price. The ATO treats GST as one-eleventh of a GST-inclusive taxable amount, so you divide that amount by 11. A $1,100 inclusive price contains $100 of GST. On a Business Activity Statement, GST on taxable sales is worked out the same way.
Who needs to register for GST?
The ATO requires GST registration if you carry on an enterprise and your GST turnover is $75,000 or more ($150,000 or more for a non-profit organisation), or if you provide taxi travel including ride-sourcing. You can register voluntarily below the threshold. Registration rules are on the ATO GST pages and are separate from this calculator.
Does every sale include GST?
No. GST-free sales (for example many basic foods, some education and some medical supplies) and input-taxed sales (for example most residential rent and financial supplies) are treated differently. This tool only applies the 10% taxable-supply method. Check the ATO lists before you treat a sale as taxable.
Is this tax advice?
No. This page is general information so you can see how the 10% rate and the divide-by-11 method work. It is not financial, tax or product advice. Confirm figures on a tax invoice and with the ATO or a registered tax practitioner before you lodge an activity statement.