Calculator

Whether you’re a small business owner, sole trader, freelancer, or just need a quick GST figure, our free Australian GST calculators make it simple. All tools are built for Australia’s standard 10% GST rate and are updated for 2025–26.

Reverse GST Calculator

Already have a GST-inclusive price and need to strip the GST out? Our Reverse GST Calculator works backwards from the total to give you the pre-GST amount and the exact GST component — no manual maths required.

Add GST Calculator

Start with a GST-exclusive (net) price and need to add 10%? The Add GST Calculator instantly shows you the GST amount and the final GST-inclusive total, ready for invoices or quotes.

GST Inclusive Calculator

Enter a GST-inclusive price to break it down into the net amount and the GST portion. Ideal for reconciling receipts, BAS reporting, or checking supplier invoices.

GST Exclusive Calculator

Enter a GST-exclusive price to instantly calculate the GST and total payable. Perfect for quoting clients or preparing tax invoices.

BAS GST Calculator

Preparing your Business Activity Statement? Our BAS GST Calculator helps you tally up GST collected and GST credits so you can complete your BAS with confidence.


Specialist GST Calculators

GST on Used Cars Calculator

GST on second-hand vehicles can be tricky — it depends on whether the seller is registered for GST and how the sale is structured. This calculator takes the guesswork out of used car GST in Australia.

GST on Airbnb Calculator

Not sure if your short-term rental income attracts GST? This calculator helps Airbnb hosts determine their GST obligations based on their annual turnover.

GST on Uber Calculator

Rideshare drivers must register for GST from their very first trip — no $75,000 threshold applies. Use this calculator to work out GST on your Uber earnings quickly and accurately.


Helpful GST Guides

Not sure how GST works? Our guides break it all down in plain English:

Why Use Our GST Calculators?

  • Free to use — no sign-up, no fees
  • Built for Australia — reflects the current 10% GST rate
  • Fast and accurate — results update instantly
  • Mobile-friendly — works on any device
  • Covers every scenario — from BAS lodgements to rideshare and short-term rentals