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GST Calculator

Result

Calculated result -1 Based on the values entered.
↗ Finance

GST Calculator (17%) GST Calculator (17%) is a financial calculator that helps you calculate tax amounts on income, purchases, or transactions. The formula used is: Add GST: Gross = Net × 1.17 · Extract GST: Net = Gross ÷ 1.17 · GST = Gross − Net. Enter m — free online calculator.

Formula

Add GST: Gross = Net × 1.17 · Extract GST: Net = Gross ÷ 1.17 · GST = Gross − Net
  • GST Calculator calculates its result from Gross, Net. It uses the formula Add GST: Gross = Net × 1.17 · Extract GST: Net = Gross ÷ 1.17 · GST = Gross − Net. Change any input to recalculate the result instantly.
  • The main inputs are Gross, Net. Enter them in the units and format shown in the calculator.
  • Use monetary amounts, rates and time periods exactly as labeled; the result reflects the assumptions entered on this page.
  • Changing any input above recalculates the result with the same calculation engine used by this page.

Example: GST

Inputs
  • Gross: 2
  • Net: 3

Using Gross = 2, Net = 3, the calculated result is -1.

Sample result: Calculating…

Frequently asked questions

What does the GST calculate?

GST Calculator (17%) GST Calculator (17%) is a financial calculator that helps you calculate tax amounts on income, purchases, or transactions. The formula used is: Add GST: Gross = Net × 1.17 · Extract GST: Net = Gross ÷ 1.17 · GST = Gross − Net. Enter m — free online calculator.

Which values should I enter?

Enter Gross, Net using the units and format shown beside each field.

What formula does this calculator use?

The calculator uses the following relationship: Add GST: Gross = Net × 1.17 · Extract GST: Net = Gross ÷ 1.17 · GST = Gross − Net.

Why might my result differ from another source?

Results can differ when another source uses different units, rounding rules, conventions or assumptions. Compare the inputs and definitions before comparing results.

Does the result update automatically?

Yes. Changing an input updates the result using the same calculation engine shown on this page.

Page information

Updated: October 7, 2026