Add or remove GST instantly · build a mixed-item invoice · check the registration threshold
Add line items below — mark any GST-free items (e.g. basic food, some health services) so they're excluded from the GST calculation automatically. Amounts are entered as GST-exclusive.
Indicative categories only — always confirm the GST status of specific goods or services on ato.gov.au.
⚠️ This calculator provides general estimates only for the 2026 10% GST rate and does not constitute tax advice. GST status of specific goods and services, registration obligations, and BAS reporting requirements can vary — always confirm with the Australian Taxation Office (ATO) or a registered tax agent. This tool is not affiliated with the ATO.
Use our free GST Calculator to add or remove Australia's 10% Goods and Services Tax from any amount in seconds. Build a multi-item invoice that automatically handles a mix of taxable and GST-free items, and check whether your business needs to register for GST based on the current turnover thresholds. Built for sole traders, small businesses, bookkeepers, and anyone who needs a fast, accurate GST figure.
GST (Goods and Services Tax) is a broad-based tax of 10% on most goods, services, and other items sold or consumed in Australia. It was introduced on 1 July 2000 and has remained at 10% ever since. Businesses registered for GST collect it on behalf of the government on their taxable sales, and can generally claim credits for the GST included in the price of things they buy for their business (known as GST credits or input tax credits).
There are two directions you might need to calculate GST, and each uses a different formula:
| You have | You want | Formula | Example |
|---|---|---|---|
| GST-exclusive price | GST amount | Price × 0.10 | $100 × 0.10 = $10 |
| GST-exclusive price | GST-inclusive price | Price × 1.10 | $100 × 1.10 = $110 |
| GST-inclusive price | GST-exclusive price | Price ÷ 1.10 | $110 ÷ 1.10 = $100 |
| GST-inclusive price | GST amount | Price ÷ 11 | $110 ÷ 11 = $10 |
The "divide by 11" shortcut works because a GST-inclusive price represents 11 equal parts (10 parts for the exclusive amount, plus 1 part for the 10% GST). This is the fastest way to pull the GST component directly out of a total that already includes GST, without needing a calculator for the intermediate exclusive amount.
You are required to register for GST in Australia if:
Businesses below these thresholds can still register voluntarily, which allows you to claim GST credits on business purchases — but it also means you must charge GST on your taxable sales and lodge regular Business Activity Statements (BAS).
Not everything attracts GST. Australian tax law splits sales into three broad categories:
If you're registered for GST and sell more than $82.50 (including GST) worth of taxable goods or services, the buyer can request a tax invoice — and for sales of $1,000 or more, the buyer's identity or ABN must also be included. A valid tax invoice generally needs to show: your identity and ABN, the words "tax invoice", the date of issue, a description of the items sold, the GST-inclusive price, and the amount of GST payable (or a statement that the price includes GST).
Once registered for GST, you'll need to report and pay GST to the ATO through a Business Activity Statement (BAS), generally lodged monthly, quarterly, or annually depending on your turnover and reporting category. Your BAS reconciles the GST you've collected on sales against the GST credits you're claiming on purchases, with the net amount payable (or refundable) reported to the ATO.
The Goods and Services Tax (GST) rate in Australia is 10%. It has remained unchanged since GST was introduced on 1 July 2000. GST applies to most goods, services, and other items sold or consumed in Australia, with some categories being GST-free or input-taxed.
To add GST to a GST-exclusive price, multiply the amount by 1.1. For example, $100 plus 10% GST equals $110. The GST component itself is the exclusive amount multiplied by 0.10 — in this example, $10.
To find the GST-exclusive amount from a GST-inclusive price, divide the total by 1.1. To find just the GST component within a GST-inclusive price, divide the total by 11. For example, a $110 GST-inclusive price has a GST-exclusive value of $100 and a GST component of $10.
You must register for GST if your business has a GST turnover of $75,000 or more per year, or $150,000 or more for non-profit organisations. Taxi and ride-sourcing drivers must register for GST regardless of turnover. Businesses under the threshold can register voluntarily.
Common GST-free categories include most basic food items, most health and medical services, education courses, exported goods and services, and most childcare. GST is still not charged on these items, but registered businesses can generally still claim GST credits on related purchases.
Both mean no GST is charged on the sale, but the treatment of GST credits differs. For GST-free sales, you can still claim GST credits on related business purchases. For input-taxed sales — such as residential rent or most financial supplies — you generally cannot claim GST credits on the related purchases.