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GST calculator (Australia, 10%)
Add GST to a price or work out how much GST is inside one. It runs in your browser with no sign-up, and nothing you type is sent anywhere.
The rules in plain English
- To remove GST, divide the GST-inclusive price by 11. That gives the GST portion. For example, $110 includes $10 GST.
- To add GST, multiply the ex-GST price by 1.1.
- You must register within 21 days of your GST turnover reaching (or being expected to reach) $75,000 in a 12-month period. The threshold for not-for-profits is $150,000. Taxi and rideshare drivers have to register from their first dollar. See the ATO's Registering for GST page, or our GST and BAS tracker guide.
- If you aren't registered, don't charge GST or put "GST" on your invoices.
- Once you're registered, you lodge a BAS (usually quarterly). You claim back the GST you paid on business purchases and pay the GST you collected.
This is general information, not tax advice. Also useful: the tax set-aside calculator and the guide to markup vs margin after fees and GST.
Want the spreadsheet version?
Our Markup & Margin Calculator (US$9.99) handles GST when you price products. The AU Small Business Starter Bundle (US$24.99) includes a GST/BAS tracker. Both are our own products. Prefer something free? Grab the free budget planner.
US$9.99 one-time on Whop. Instant download.
See it on Whop →General information only, not financial, tax or legal advice. Last checked 16 Nov 2026.