GST Calculator

To calculate GST in Australia, multiply a GST-exclusive price by 0.1 to get the GST amount, or divide a GST-inclusive price by 11. Multiply by 1.1 to get the GST-inclusive price, and divide by 1.1 to get the GST-exclusive price.

The GST calculator above runs those 4 calculations for you in 3 steps:

1. Choose Add GST when the price excludes GST, or Remove GST when the price includes GST.
2. Type the amount in Australian dollars (AUD). The 10% GST rate is already set.
3. Read the GST amount, the amount excluding GST and the amount including GST, and copy any figure with one click.

Results update as you type, so there’s no Calculate button to press. Every calculation runs in your browser, and nothing you enter is sent anywhere.

GST in Australia is a 10% tax on most goods, services and other items sold or consumed in the country. Businesses registered for GST collect it on sales and pass it to the Australian Taxation Office (ATO).

GST is the Goods and Services Tax, a broad-based federal tax of 10% on most goods and services sold or consumed in Australia. GST is a value-added tax: each GST-registered business in a supply chain charges GST on its sales and claims back the GST on its purchases, so the end consumer carries the full 10%.

The Howard Government introduced GST on 1 July 2000, under A New Tax System (Goods and Services Tax) Act 1999. GST replaced the wholesale sales tax and several state taxes. The ATO administers GST, and the GST collected goes to the states and territories.

The current GST rate in Australia is 10%. The 10% GST rate has not changed since GST started in July 2000. The GST rate in Australia has 4 main features:

• Flat rate. One 10% rate applies to every taxable sale. Australia has no GST rate slabs.
• National rate. The same rate applies in every state and territory, including NSW, Victoria, Queensland, WA, SA, Tasmania, the ACT and the NT.
• Broad base. GST applies to most goods, services, imports and digital products.
• Set exemptions. Some sales are GST-free or input-taxed and carry no GST, such as most basic food, many health services and residential rent.

GST is calculated as 10% of the GST-exclusive price. A GST-exclusive price is the price before GST is added. A GST-inclusive price is the price after GST is added, and it’s the price a consumer pays.

GST calculation works in 2 directions:

• Adding GST to a price. Take 10% of the GST-exclusive price and add it on. A $1,000 sale becomes $1,100.
• Subtracting GST from a price. Take one-eleventh of the GST-inclusive price. A $1,100 total contains $100 of GST.

The GST in a GST-inclusive price is one-eleventh, not 10%. A GST-inclusive price is 110% of the original price: 100 parts of price plus 10 parts of GST. GST is 10 of those 110 parts, which is 1/11, or about 9.09% of the total.

The GST formula is GST amount = original price × GST rate ÷ 100. At the 10% GST rate, that’s the original price × 0.1.

The general formulas work for any GST rate:

• GST amount (adding GST) = original price × GST rate ÷ 100
• GST-inclusive price = original price × (1 + GST rate ÷ 100)
• GST amount (removing GST) = GST-inclusive price × GST rate ÷ (100 + GST rate)
• GST-exclusive price = GST-inclusive price × 100 ÷ (100 + GST rate)

The GST calculator does 5 jobs: adding GST, removing GST, finding the GST amount, checking GST-inclusive and GST-exclusive prices, and calculating GST at other rates.

• Add GST (Plus GST mode). The calculator converts a GST-exclusive price into a GST-inclusive price, for quotes, invoices and price lists.
• Remove GST (Minus GST mode). The calculator works as an ex GST calculator and a reverse GST calculator. It splits a GST-inclusive total into the GST-exclusive price and the GST amount.
• Find the GST amount. The calculator shows the GST on its own, ready for a tax invoice or your business activity statement (BAS).
• Check inclusive and exclusive prices. The calculator shows the GST-inclusive and GST-exclusive figures side by side, so you can compare 2 quotes priced differently.
• Calculate other rates. The Change rate link sets any rate from 0.01% to 100%, such as New Zealand’s 15% GST.

The calculator has 6 parts: the Add GST and Remove GST toggle, the amount input, the GST rate field, the result display, the copy buttons and the Reset button. Results round to the nearest cent, with half a cent rounded up.

For a page set to one mode, use the Add GST calculator or the Remove GST calculator.

To use a GST calculator in Australia, follow 5 steps.

Step 1: Check your starting price. Look for “inc GST” or “ex GST” on the invoice, quote or receipt. Retail prices for consumers in Australia must include GST. Business quotes and wholesale prices often exclude GST.

Step 2: Add GST to a GST-exclusive price. Choose Add GST and type the price. The calculator multiplies the price by 1.1 and shows the total your customer pays.

Step 3: Remove GST from a GST-inclusive price. Choose Remove GST and type the total. The calculator divides the total by 1.1 and shows the price before GST. Use Remove GST for supplier bills and to work out your profit on a sale.

Step 4: Read the GST amount. The GST amount line shows the tax on its own. The GST amount is the figure you report on your BAS: GST on sales, or GST credits on purchases.

Step 5: Check the answer. The GST amount equals 10% of the GST-exclusive price. Start again with the other mode, if the GST amount doesn’t match.

These 5 worked examples use the 10% GST rate.

• Adding GST to a quote. A plumber quotes $640 before GST. $640 × 0.1 = $64 GST, so the invoice total is $704.
• Removing GST from an invoice. An invoice shows $220 including GST. $220 ÷ 1.1 = $200 before GST, and the GST amount is $20.
• Finding the GST in a receipt. A receipt shows $1,000 including GST. $1,000 ÷ 11 = $90.91 GST, and the GST-exclusive price is $909.09.
• Pricing a product. A café sells a hamper for $55 including GST. $55 ÷ 1.1 = $50 before GST, so $5 of each sale is GST owed to the ATO.
• Calculating GST on imported goods. A GST-registered retailer imports stock with a customs value of $30,000, plus $1,500 customs duty and $2,000 transport and insurance. GST applies to the $33,500 total: $33,500 × 0.1 = $3,350 GST, which the retailer can claim back as a GST credit.

The table below shows GST on common amounts, calculated by the same rules as the calculator.

There are 5 common GST calculator mistakes:

1. Taking 10% off a GST-inclusive price. $220 minus 10% is $198, but the price before GST is $200. Divide by 1.1 to remove GST.
2. Adding GST to a price that already includes GST. Adding GST twice overcharges the customer by 10% and needs an adjustment note to fix.
3. Dividing a mixed receipt by 11. A $120 supermarket receipt with $70 of GST-free fresh food contains GST only on the $50 of taxable items: $50 ÷ 11 = $4.55, not $10.91.
4. Charging GST without registration. A business that isn’t registered for GST can’t charge GST or show GST on its invoices.
5. Rounding each step. Round the final GST amount to the cent, not the numbers along the way.

GST credits are the GST a registered business claims back from the ATO for the GST included in its business purchases. A business claims GST credits on its BAS, and the credits reduce the GST the business owes on its sales.

A bookkeeper buys a laptop for $1,650 including GST, for business use only. $1,650 ÷ 11 = $150 GST, so the bookkeeper’s business claims a $150 GST credit on the next BAS. If GST credits are higher than the GST collected on sales, the ATO refunds the difference.

To claim GST credits, a business meets 4 conditions:

• Registration. The business is registered for GST.
• Business use. The purchase is for the business, or the business claims only the business share.
• GST in the price. The price includes GST. GST-free purchases carry no GST credit.
• Tax invoice. The business holds a tax invoice for purchases over $82.50 including GST.

GST-free items in Australia include most basic food, many health and medical services, most education courses, childcare and exports. GST-free supplies carry no GST, and the seller can still claim GST credits on the costs of making them.

There are 8 common groups of GST-free supplies:

• Basic food. Fresh fruit, vegetables, meat, eggs, milk and plain bread.
• Health services. Many medical, health and care services, and some medicines.
• Medical aids. Some medical aids and appliances for people with an illness or disability.
• Education. Most education courses. Textbooks and stationery are often taxable.
• Childcare. Approved childcare services.
• Exports. Goods and services exported from Australia.
• Water and sewerage. Water, sewerage and drainage services.
• Menstrual products. Pads, tampons and similar products.

Prepared food, takeaway meals, soft drinks, confectionery and snacks are taxable. Financial services and residential rent are input-taxed: they carry no GST, and the seller can’t claim GST credits on related costs. The ATO’s GST-free sales guide lists the exceptions for each group.

Thriday is an Australian financial platform for small businesses that combines a business transaction account with bookkeeping and tax tools. All-in-one platforms such as Thriday track the GST on each sale and purchase, so the GST amounts for your BAS are ready at the end of each period.

Banking and accounting software helps with GST in 4 ways:

• Automatic GST coding. Each transaction is tagged as taxable, GST-free or input-taxed.
• GST put aside. The GST you collect is kept separate from your spending money.
• BAS figures. GST on sales and GST credits on purchases are totalled for each quarter.
• Receipt storage. Tax invoices are saved against each purchase for GST credit claims.

A GST calculator checks single amounts. Accounting software tracks GST across every invoice and receipt in a quarter. Check each provider’s current features and fees before you sign up.