Free GST Calculator
for Australia

Calculate GST instantly on any amount. Add or remove the standard Australian 10% GST.
A free online tool for freelancers and small businesses.

GST Calculator
Add or remove the standard Australian 10% GST
$
Amount (ex. GST)$0.00
GST (10%)$0.00
Total (inc. GST)$0.00

Formula: GST = Amount × 0.10, Total = Amount × 1.10

How Does GST Work in Australia?

Everything you need to know about GST (Goods and Services Tax)

What is GST?

GST is a 10% tax applied to most goods and services. If you run a business in Australia, you need to charge this tax and remit it to the Australian Taxation Office (ATO).

Extracting GST from GST-Inclusive Prices

To calculate the GST amount from the total price, divide by 11.

GST = Total ÷ 11
Example: $110 ÷ 11 = $10 (GST)

Adding GST to GST-Exclusive Prices

To add GST to the base amount, multiply by 10% or multiply by 1.1.

GST = Amount × 0.10
Total = Amount × 1.10
Example: $100 × 1.10 = $110 (Total)

GST Registration Threshold

If your annual turnover is $75,000 or more, GST registration is mandatory. If your turnover is below this threshold, you can voluntarily register and claim GST credits on business expenses.

Tax Invoice Requirements

GST-registered businesses must include the following on Tax Invoices:

  • The words "Tax Invoice"
  • Seller's ABN (Australian Business Number)
  • Seller's business name
  • Issue date
  • Description of goods/services
  • GST amount
  • Total amount

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