Can this tool replace professional tax advice?

No. The tool is an educational calculation aid. Users should verify figures, legal classification, rates and due dates with a qualified professional before making decisions.

Does the tool store my calculation?

Standard tool calculations are processed in the browser request and can be shared using the generated URL. Avoid entering confidential case information on public pages.

Invoice Total Calculator | GST Taxable Value and Discount

Purpose

The invoice total calculator estimates taxable value after discount, GST amount and final total.

Taxable value = Amount − Discount
GST = Taxable value × GST rate ÷ 100
Total = Taxable value + GST

Limitations

Discount treatment under GST depends on invoice terms, agreements, credit notes and statutory conditions. Confirm the legal position before reducing taxable value.

Frequently asked questions

Can post-supply discounts reduce GST?

Only where statutory conditions and documentation requirements are satisfied.