Knowing how to calculate gst can help you work out the Goods and Services Tax charged on taxable goods and services in Australia. Whether you are preparing an invoice, checking a purchase price or setting a business price, understanding GST calculations can make financial tasks easier.
Australia’s standard GST rate is 10% for most taxable goods and services. Learning how to calculate gst allows you to find the GST amount, add GST to a price, or identify the GST included in a total amount.
Goods and Services Tax, commonly known as GST, is a broad-based tax applied to most goods and services sold or consumed in Australia. The standard rate is 10%, although some supplies have different GST treatment.
When a price is GST-exclusive, GST is added to the original amount. When a price is GST-inclusive, the GST is already included in the total.
Businesses may need to calculate gst when preparing quotes, invoices, financial records and customer prices. Consumers may also want to understand how much GST is included in the price they pay.
Knowing the GST component can make it easier to understand the difference between the original price and the final amount.
To calculate gst on a GST-exclusive amount using the standard 10% rate, multiply the original price by 10%.
For example, if a product costs $600 before GST:
$600 × 10% = $60 GST
The total price including GST is therefore $660.
If the price already includes GST, you can calculate gst by dividing the GST-inclusive total by 11.
For example, if the total price is $1,100:
$1,100 ÷ 11 = $100 GST
The price before GST is therefore $1,000.
To calculate gst on an amount excluding GST, use:
GST = GST-exclusive price × 10%
To find the total including GST:
GST-inclusive price = GST-exclusive price + GST
For example, a $2,500 GST-exclusive amount has $250 GST, resulting in a total of $2,750.
When GST is already included in the total, use:
GST = GST-inclusive price ÷ 11
For example, if the total is $3,300, the GST component is $300 and the amount before GST is $3,000.
Manually calculating GST is easy for individual amounts, but repeated calculations can become time-consuming. An online calculator can calculate gst quickly and reduce the need for manual formulas.
This can be useful when checking several invoices, expenses, products or services.
Businesses can use GST calculations to check whether invoices and quotes contain the correct GST amount. This can also make it easier to separate GST from the underlying price.
Using a calculator to calculate gst provides a quick way to verify your figures before completing a transaction.
Suppose a business sells a taxable service for $1,800 before GST. To calculate gst, multiply $1,800 by 10%.
The GST is $180, making the total GST-inclusive price $1,980.
If you instead have a GST-inclusive total of $1,980, dividing it by 11 gives $180 GST. The amount before GST is therefore $1,800.
To calculate gst on a GST-exclusive amount at the standard 10% rate, multiply the amount by 10%. Add the GST to the original amount to find the total including GST.
If the price already includes standard 10% GST, divide the total by 11 to find the GST component.
The standard GST rate in Australia is 10% for most taxable goods and services.
If $500 is GST-exclusive, 10% GST is $50, making the total $550 including GST.
If $550 is GST-inclusive, the GST component is $50 and the amount before GST is $500.
If $1,000 is GST-exclusive, the GST is $100 and the GST-inclusive total is $1,100.
Yes. For a standard GST-inclusive amount, divide the total by 11 to find the GST component.
No. Some goods and services may be GST-free or have different GST treatment. The applicable Australian tax rules should be checked for the specific transaction.