Free Australian GST Calculator
Add or remove 10% GST in seconds and see the net amount, GST and total — no formulas, no spreadsheets.
GST rate — standard is 10%
GST treatment
Result
Total amount incl. GST
$ 1,100.00
Net amount (ex-GST)
$1,000.00
GST @ 10%
$100.00
$1,000.00
Net + $100.00
GST = $1,100.00
Total
Net + $100.00
GST = $1,100.00
Total
How to calculate GST in Australia
This free Australian GST calculator does the math for you in three quick steps — whether you need to add GST to a price or remove GST from a price that already includes it.
1
Enter the amount
Type the price of your goods or service in AUD.
2
Choose the GST rate
Use 10% (standard), 0% (GST-free) or set a custom rate.
3
Add or remove GST
Pick whether the amount excludes or includes GST — the result updates instantly.
What is GST in Australia?
The Goods and Services Tax (GST) is a broad-based, consumption tax of 10% on most goods, services and other items sold or consumed in Australia. It was introduced on 1 July 2000 and is administered by the Australian Taxation Office (ATO), applying uniformly across all states and territories. GST-registered businesses collect GST on their sales, claim credits for the GST on their purchases (input tax credits), and report the difference to the ATO on a Business Activity Statement (BAS).
Australian GST categories
| Category | Rate | Typical examples |
|---|---|---|
| Taxable | 10% | Most goods & services sold in Australia — you charge GST and can claim credits on related costs |
| GST-free | 0% | Most basic food, many medical & health services, some education and childcare, and exports — no GST charged, but you can still claim credits |
| Input-taxed | No GST | Residential rent and most financial supplies — no GST charged, and you cannot claim credits on related costs |
| Out-of-scope | — | Supplies that aren’t connected with Australia or aren’t taxable supplies |
GST-free vs input-taxed: both mean no GST is charged to the customer, but the difference matters for credits — businesses making GST-free supplies can still claim GST credits on related purchases, while those making input-taxed supplies generally cannot. Always confirm your supply’s classification with the ATO or a registered tax agent.
Who needs to register for GST?
You must register for GST with the ATO if any of these apply:
Mandatory
Your business has a GST turnover of $75,000 or more in a 12-month period (current or projected).
Non-profit
Non-profit organisations register once turnover reaches $150,000. Taxi and ride-sourcing drivers must register regardless of turnover.
GST calculation formula (with examples)
Prefer to see the maths? These are the exact formulas the calculator uses, with worked examples at the Australian 10% rate.
Read this first
In every formula below, “GST Rate” is the percentage you charge — for Australia that is 10. To avoid mixing 10 and 0.10, all formulas keep the same form: GST Rate ÷ 100. So at 10%, GST Rate ÷ 100 = 0.10 and 1 + GST Rate ÷ 100 = 1.10.
+Adding GST price excludes GST
GST = Net Price × (GST Rate ÷ 100)
Total = Net Price + GST
Example — net $100 at 10%
GST= 100 × (10 ÷ 100) = $10.00
Total= 100 + 10 = $110.00
−Removing GST price includes GST
Net Price = Inclusive Price ÷ 1.1
GST = Inclusive Price ÷ 11
Example — gross $110 incl. GST at 10%
Net= 110 ÷ 1.1 = $100.00
GST= 110 ÷ 11 = $10.00
=Quick total net → total in one step
Total = Net Price × 1.1
GST = Total − Net Price
Example — net $100 at 10%
Total= 100 × 1.1 = $110.00
GST= 110 − 100 = $10.00
The reverse trick: GST is exactly 1/11th of a GST-inclusive price (because 10% of 110% = 1/11). Don’t take 10% of the total — that overstates the GST. Figures are rounded to 2 decimal places (cents).
Frequently asked questions
What is the GST rate in Australia?
The GST rate in Australia is a flat 10% on most goods and services. It was introduced on 1 July 2000 and is administered by the Australian Taxation Office (ATO). Some supplies are GST-free (0%) or input-taxed.
How do I add 10% GST to a price?
Multiply the GST-exclusive (net) amount by 1.1 to get the GST-inclusive total, or by 0.1 to get the GST itself. Example: $1,000 × 1.1 = $1,100, so the GST is $100.
How do I remove GST from a GST-inclusive price?
Divide the total by 1.1 to get the net (GST-exclusive) price, or divide by 11 to get the GST component. Example: $1,100 ÷ 1.1 = $1,000 net, and $1,100 ÷ 11 = $100 GST.
Why divide by 11 and not take 10%?
Because the GST is 10% of the net price, not of the total. The total is 110% of the net, so the GST is 10/110 = 1/11 of the inclusive price. Taking 10% of the total overstates the GST.
What’s the difference between GST-free and input-taxed?
Both mean no GST is charged to the customer. The difference is credits: businesses making GST-free supplies can still claim GST credits on related purchases, while those making input-taxed supplies generally cannot.
When must a business register for GST?
You must register once your GST turnover reaches $75,000 in a 12-month period ($150,000 for non-profits). Taxi and ride-sourcing drivers must register regardless of turnover. You can also register voluntarily below the threshold.
Is this GST calculator free?
Yes. The ProfitBooks Australian GST calculator is completely free, needs no sign-up, works on mobile and desktop, and updates instantly as you type.
Keep your GST in order, every invoice
ProfitBooks helps you raise GST-compliant invoices, track GST collected and paid, and keep your books ready for your BAS — so you spend less time on tax and more on your business.
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This calculator is for general guidance only and reflects the Australian standard GST rate of 10%. It is not tax advice — GST classification (taxable, GST-free, input-taxed) can be complex, so confirm treatment with the ATO or a registered tax agent before lodging your BAS.
