To add GST to a price:
Once you have GST from a government website or previously calculated in Omnicalculator's tool: Indian - Australian GST calculator, verify you have the net price, also called GST exclusive price.
Express the percentage as a decimal value. For example, if GST is 10%, write it down as 0.10. If GST is 15%, then you have 0.15.
Add 1 to the GST decimal value. Multiply the result by the net price. Congratulations, you have your price GST inclusive.
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