Australian GST Calculator
Calculate Australia's 10% GST in both directions: add it onto a quoted ex-GST price, or extract the GST that's already baked into a GST-inclusive total. The calculator shows the ex-GST net, the GST line item, and the gross side by side — useful for invoicing, BAS reconciling, and quick price checks.
How to use the GST calculator
- Pick a direction. Switch between Add GST (you have an ex-GST price and want the inclusive total) and Remove GST (you have an inclusive total and want the GST or the net).
- Enter the amount in Australian dollars. Use the slider for quick exploration or type any value into the input.
- Read the breakdown. The hero shows the most relevant figure for your direction; below it, all three values (ex-GST, GST, inc-GST) appear together so you can copy whichever you need.
The two formulas
- Add GST
inclusive = ex-GST × 1.10andGST = ex-GST × 0.10.- Remove GST
ex-GST = inclusive ÷ 1.10andGST = inclusive ÷ 11.
The shortcut for extracting GST from a total is “divide by 11”. That's because the gross is 110% of the net, so the GST line is exactly 1/11 of the gross — about 9.09%, not 10%. This is a common confusion: 10% is the rate on the net, but only about 9.09% of the gross.
Worked examples
- A$200 ex-GST → A$220 inclusive. GST is A$20. You'd quote this on an invoice as: subtotal A$200, GST A$20, total A$220.
- A$77 receipt → A$70 net, A$7 GST. Divide A$77 by 11 to get A$7; subtract to get A$70 net.
- A$1,000 receipt → A$909.09 net, A$90.91 GST. A$1,000 ÷ 11 ≈ A$90.91.
- A$49.95 sticker price (incl. GST) → A$45.41 net, A$4.54 GST. Common pricing pattern at retail.
GST in Australia — quick reference
- Rate
- 10% (flat, unchanged since 1 July 2000).
- Registration threshold
- A$75,000 annual turnover (A$150,000 for non-profits). Mandatory at A$0 for ride-share / taxi drivers.
- GST-free supplies
- Most fresh food, basic medical and educational services, exports.
- Input-taxed supplies
- Residential rent, most financial services — no GST charged but no input credits available either.
- BAS
- Business Activity Statement — the quarterly (or monthly) form businesses use to report GST collected and paid.
- Tax invoice
- Required for sales of A$82.50 or more (incl. GST). Must show the supplier's ABN, the GST amount, and a few standard fields.
Frequently asked questions
- Is GST always 10% in Australia?
- Yes — the rate hasn't changed since GST was introduced in 2000. Some items are GST-free or input-taxed, but the rate itself is fixed at 10%.
- Does this calculator handle currency conversion?
- No, it works in Australian dollars. To convert other currencies to AUD first, use the Currency Converter.
- Can I use this for New Zealand GST?
- The mechanics are the same but New Zealand's GST rate is 15%, not 10%. This calculator hardcodes 10% for Australia.
- Is this official ATO advice?
- No — the calculator is a maths tool. For tax-treatment questions on specific transactions or whether you must register, refer to the Australian Taxation Office or a registered tax agent.