GST Calculator Australia
Add 10% GST to a net price or remove GST from an inclusive total. Instant, free and private, with the maths done on your device.
Australian GST is a flat 10% on most goods and services.
Figures rounded to 2 decimals (cents). Verify GST-free and input-taxed treatment against current ATO guidance.
How to add or remove GST in Australia
Australian GST is a flat 10%. To add GST to a net price, multiply by 1.1: an A$100 quote becomes A$110 including GST. To remove GST from a price that already includes it, divide by 1.1: A$110 ÷ 1.1 = A$100 net, with A$10 of GST.
A handy cross-check: the GST component of a GST-inclusive price is exactly one-eleventh of the total. On A$220 inclusive, the GST is A$20. This is the same fraction the ATO uses when working out GST from a total on an activity statement.
Some supplies are GST-free, including most basic food, health and medical services, education and childcare, and exports; others such as residential rent and financial supplies are input-taxed. Businesses must register for GST, using their ABN, once GST turnover reaches A$75,000 in any 12-month period (A$150,000 for non-profits).
GST at a glance: common amounts
| Net (excluding GST) | GST at 10% | Total (including GST) |
|---|---|---|
| A$50.00 | A$5.00 | A$55.00 |
| A 00.00 | A 0.00 | A 10.00 |
| A$250.00 | A$25.00 | A$275.00 |
| A ,000.00 | A 00.00 | A ,100.00 |
| A$4,545.45 | A$454.55 | A$5,000.00 |
The last row runs the calculation backwards: an A$5,000 GST-inclusive price contains A$454.55 of GST (one-eleventh of the total), leaving A$4,545.45 net.
Tax invoices and the BAS in Australia
A GST-registered seller must issue a tax invoice for any taxable sale of A$82.50 or more (GST inclusive) when the buyer asks for one, and has 28 days to do it. The invoice has to show the words "tax invoice", the seller's identity and ABN, the date, a description of what was sold, and either the GST amount for each line or a statement that the total includes GST. For sales of A ,000 or more it must also show the buyer's identity or ABN. Below A$82.50 a receipt or bank record is enough to support a GST credit.
GST collected and paid is reported on the business activity statement (BAS). Most businesses lodge quarterly; monthly lodgement becomes compulsory once GST turnover reaches A$20 million, and businesses registered voluntarily under the A$75,000 threshold can elect to report annually. On the BAS, label 1A carries the GST on sales and 1B the GST on purchases, and the difference is what you pay or receive. Because Australian GST is a single 10% rate, the one-eleventh rule this calculator uses is exactly how the ATO expects GST to be extracted from a GST-inclusive figure.
Frequently asked questions
What is the GST rate in Australia?
Australia charges a single flat GST rate of 10% on most goods and services. The rate has been 10% since GST was introduced on 1 July 2000. Some items are GST-free, including most basic food, health and medical services, and education.
How do I take GST out of a GST-inclusive price?
Divide the GST-inclusive amount by 1.1. For A$110 inclusive: 110 ÷ 1.1 = A$100 net, so the GST component is A$10. Equivalently, the GST portion of an inclusive price is exactly one-eleventh of the total.
Which items are GST-free in Australia?
Common GST-free categories include most basic food, health and medical services, education courses, childcare, and exports. GST-free sales have no GST in the price but still count towards the A$75,000 registration turnover threshold, and registered businesses can claim GST credits on related purchases.
When do I need to register for GST in Australia?
You must register within 21 days once your GST turnover reaches A$75,000 in any 12-month period (current or projected), or A$150,000 for non-profit organisations. You need an ABN to register. Taxi and ride-sourcing drivers must register regardless of turnover.
Is this GST calculator free?
Yes. It is free, needs no sign-up, and the calculation happens on your device, so nothing is sent to a server. No data is uploaded anywhere.