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CalculatorQuest

Australian Financial Calculators

Free GST Calculator Australia

Add, remove, or split Australian GST instantly — 10% standard rate, mobile-friendly, no signup.

Enter your figures

Calculation type

Uses the numeric keypad on phones

Australia standard is 10%

Your results

Results appear here instantly — no page jump.

Estimates only, not tax or financial advice. Results are general information based on published ATO rules and the figures you enter. For advice about your situation, speak to a registered tax agent or licensed financial adviser. How we calculate · Spotted a mistake?

GST formulas used

Australia's standard GST rate is 10%. This calculator uses the same arithmetic the ATO expects for inclusive and exclusive prices:

  • Add GST: Total = Amount × (1 + rate) · GST = Amount × rate
  • Remove GST: Base = Inclusive ÷ (1 + rate) · GST = Inclusive − Base
  • Split: GST = Inclusive × rate ÷ (1 + rate) · Base = Inclusive − GST

With rate = 0.10: multiply by 1.10 to add GST; divide by 1.10 to remove GST.

Worked example: $220 invoice (GST inclusive)

  1. You receive a quote of $220 including GST at the 10% rate.
  2. Base (ex-GST) = 220 ÷ 1.10 = $200.00
  3. GST component = 220 − 200 = $20.00
  4. Check: 200 × 0.10 = $20 and 200 + 20 = $220. Select Remove GST or Split GST above and enter 220 to verify.

Frequently Asked Questions

What is the GST rate in Australia?
The standard Goods and Services Tax (GST) rate in Australia is 10%. Most goods and services are taxable at this rate. Some items (basic food, some health and education services) are GST-free.
How do I add GST to a price?
Multiply the GST-exclusive amount by 1.10 (or add 10%). Example: $100 + 10% GST = $110 total. GST component = $10.
How do I remove GST from an inclusive price?
Divide the GST-inclusive amount by 1.10. Example: $110 ÷ 1.10 = $100 base. GST component = $10. Or use: GST = inclusive × (10 ÷ 110).
Is this calculator free to use?
Yes. The CalculatorQuest GST calculator is free, runs in your browser, and does not require an account. Figures are estimates for general information only.

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