About IGST Calculator
IGST (Integrated Goods and Services Tax) is levied under the IGST Act 2017 on all inter-state supplies of goods and services (where the supplier and recipient are in different states or union territories).
Unlike intra-state sales which split tax into CGST + SGST, inter-state sales apply 100% of the tax rate as IGST, collected directly by the Central Government and subsequently apportioned to the destination state.
IGST also applies to imports of goods and services into India and supplies made to or by SEZ (Special Economic Zone) units.
IGST Calculation Formula
IGST Amount = Base Amount × (Full GST Rate ÷ 100)Base Amount = Total Price × 100 ÷ (100 + IGST Rate)There is no split between CGST and SGST for IGST transactions. Full tax rate applies as IGST.
Example: Interstate Sale of Machinery (₹1,00,000 at 18% IGST)
A machinery manufacturer in Delhi sells industrial equipment to a buyer in Gurgaon, Haryana.
Because Delhi and Haryana are different states, 100% of the ₹18,000 tax is charged as IGST.