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Australian business tax
GST Calculator Australia
Add or remove GST from a price for Australian invoices, quotes, and basic business pricing decisions.
When to use this GST calculator
Use this when you need a quick GST-inclusive total for an Australian quote, invoice, checkout price, or purchase estimate.
What this estimate does not include
This page does not decide whether GST should legally apply to a transaction. Industry rules, business registration status, and special cases still need to be confirmed in your actual Australian tax setup.
What to check next
Confirm whether your starting amount is before GST or already includes GST before using the total in a customer-facing price.
Who should use this Australian GST calculator
This tool is useful for Australian freelancers, contractors, sellers, and small businesses that want to review GST-inclusive totals before sending quotes, invoices, or price estimates.
Frequently asked questions
Can I use this to remove GST from a total?
This page currently focuses on adding GST to a base amount. You can still use it as a quick estimate by comparing the added GST amount with your existing total.
Is this useful for online sellers?
Yes. It is helpful for small business pricing, invoices, and checking how tax changes the final customer-facing amount.
Example calculation
Example: if your base amount is 180 and the GST rate is 10%, the GST amount is 18 and the total becomes 198.
Related tools
Compare it with the GST Calculator NZ, the GST/HST Calculator, and the VAT Calculator.