GST Calculator
Add or extract GST at any rate.
Rates change with budgets and local ballot measures, and the rate that applies depends on the delivery address and product category. Treat these as planning figures, not as a filing.
Price including GST
$1,100.00
$100.00 of GST at 10%
GST inside a gross price is 10/110 of it — 9.09%, not 10%. At 10% the fraction is a clean one eleventh, which is why Australian bookkeeping divides by 11.
How the GST Calculator works
GST works exactly like VAT: charged on the net, so the fraction inside a gross price is rate over 100 plus rate. At 10% that is one eleventh, which is why Australian bookkeeping divides by 11 rather than multiplying by 10%.
Not financial advice. Marketplace fees change, and they vary by country, plan and seller status. Every rate here is an editable default, not a quoted price — check the platform's current fee schedule before you price a product against it. This is not tax or business advice.
Frequently asked questions
How do I calculate GST?
To add it, multiply the net by 1 plus the rate. To extract it from a GST-inclusive price, divide by the same figure. At 10%, multiply by 1.1 going forward and divide by 1.1 coming back.
Why divide by 11 at 10% GST?
Because the GST inside a gross price is 10/110, which is exactly one eleventh. Dividing the gross by 11 gives the GST directly — a shortcut that only works at 10%.
Is GST the same as VAT?
Mechanically yes — both are consumption taxes collected in stages with credit for tax paid on inputs. The name differs by country, and some systems layer federal and state components, but the arithmetic is identical.
Do I charge GST if I am not registered?
No, and you must not. You also cannot claim input credits. Registration is compulsory above each country's turnover threshold and optional below it.