GST Calculator
Add or remove 10% GST on a single taxable amount.
GST calculator
Enter a nonnegative amount and choose GST-exclusive or GST-inclusive. The standard Australian GST rate is 10% (ATO — How GST works, checked 2026-09-08). GST is rounded to the nearest cent, with 0.5 cents rounded up, as for a single taxable supply (Nearest cent, 0.5 cents upwards).
About This Tool
The Goods and Services Tax (GST) is a broad-based 10% tax on most goods, services, and other items sold or consumed in Australia. Introduced on 1 July 2000, GST is collected by registered businesses at each stage of the supply chain. Businesses can claim input tax credits for GST included in the price of goods and services they purchase for business use, meaning GST is effectively paid only by the end consumer.
Why This Matters for Australian Businesses
Accurate GST calculations are essential for correct tax invoicing, BAS reporting, and cash flow management. Common mistakes include charging GST on exempt items such as basic food, some medical services, and educational courses. Under-reporting GST on your BAS can trigger ATO audits and penalties, while over-reporting means unnecessary cash flow loss until you claim the correction on a subsequent BAS.
How to Use This Tool
- Choose GST-exclusive (add 10%) or GST-inclusive (take 1/11 of the price)
- Enter a nonnegative amount in Australian dollars
- Calculate to see net, GST and gross, each in AUD, with GST rounded to the nearest cent
Key Rules & Thresholds
- The GST rate in Australia is 10% and has not changed since its introduction in 2000
- Businesses must register for GST if annual turnover is $75,000 or more ($150,000 for non-profits)
- GST-free items include most basic food, some medical and educational services, and exports
- Input tax credits allow businesses to claim back GST paid on business purchases
- Tax invoices must show the GST amount for sales of $82.50 or more (including GST)
- The GST component of a GST-inclusive price is calculated by dividing the total by 11
How Results Are Calculated
Exclusive amounts: GST is 10% of the entered value (GST Act s 9-70), rounded to the nearest cent with 0.5 cents rounded up (s 9-90). Gross is net plus GST. Inclusive amounts: GST is 1/11 of the entered price (s 9-75), rounded the same way. Net is gross minus GST. This is a single taxable amount only — mixed supplies, GST-free items and multi-line invoice rounding options are out of scope.