Australian GST
Add GST to a taxable price or extract it from an inclusive amount.
Business planning · Reviewed 7 October 2026Your inputs
Use your business figures in AUD and the tax basis described below.
How to prepare your inputs
Use figures from your own job records, supplier invoices and business budget. Keep GST treatment consistent across inputs.
How this calculation works
Exclusive → inclusive: multiply by 1.1. Inclusive → GST: divide by 11.
$1,100 including GST contains $100 GST and $1,000 excluding GST.
Assumptions & exclusions
Uses 10% for fully taxable supplies. Does not determine registration or tax treatment. GST-free and input-taxed supplies require different treatment.
Your next step
Review pricing and cash-flow assumptions against actual completed jobs and seek advice on tax and employment treatment.
Further reading
- ATO guidance
These resources provide background information. Confirm current product specifications and project requirements with your supplier or trade professional.
What if my shape or product is different?
Use dimensions and product data that match the stated method. For complex work, calculate separate sections or obtain a project-specific take-off. Do not apply simple geometry to structural or compliance decisions.
Why are quantities rounded up?
Whole bags, packs, sheets or cartridges round up to purchasable units. Decimal area or volume results are planning figures; confirm order increments with the supplier.
Are my entries saved?
No. Entries remain in the current browser page and clear on reload. Printing can save your results and inputs as a PDF on your device.
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