Add GST to a base amount, or remove GST from a GST-inclusive price.
To add GST to a base amount: GST amount = base × (rate / 100), final price = base + GST. To remove GST from a GST-inclusive price: base = inclusive ÷ (1 + rate/100), GST amount = inclusive − base.
GST amount = base amount × (rate / 100). The final price is the base amount plus the GST amount.
Base amount = inclusive price ÷ (1 + rate/100). Subtract the base amount from the inclusive price to get the GST amount.
In India, the common GST slabs are 5%, 12%, 18%, and 28%, depending on the category of goods or services. You can also enter any custom rate.