Tools & Math
4 min read
How to Use a GST Calculator: Inclusive vs Exclusive
GST Expert Team
Updated 7 March 2026
GST Exclusive
GST Exclusive means the price of the product does not include GST. You add the GST amount on top of this price.
Formula: GST Amount = (Original Cost * GST%) / 100
GST Inclusive
GST Inclusive means the price already includes the GST amount. You need to "reverse-calculate" to find the base price.
Formula: GST Amount = Price - (Price * (100 / (100 + GST%)))
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