Multiply the base price by the GST rate, divide by 100 and add it to the price. For example, 18% GST on ₹10,000 is ₹1,800, making ₹11,800.

Base price = total ÷ (1 + rate/100). If ₹11,800 includes 18% GST, the base price is ₹10,000.

Within a state, GST is split half CGST (central) and half SGST (state). Sales from one state to another carry the full amount as IGST.

Under GST 2.0, in force since September 2025, most goods are taxed at 5% or 18%, some luxury and harmful goods at 40%, and gold and silver at 3%. Always check an item’s rate in the official list.