GST Calculator (Add or Remove GST)

GST (Goods and Services Tax) replaced most indirect taxes in India from 1 July 2017. It is a destination-based, multi-stage tax levied at four main slabs — 5%, 12%, 18% and 28%. For intra-state transactions, the GST amount is split equally into CGST (Central GST) and SGST (State GST). For inter-state transactions, the full rate applies as IGST. Businesses registered under GST can claim Input Tax Credit on GST paid for inputs, paying only the net liability.

The forward calculation adds GST to a base price to arrive at the consumer-facing total. The reverse (extraction) calculation works backward from a GST-inclusive price to find the original net value — useful for reconciling invoices where only the gross amount is known. Dividing by (1 + Rate/100) rather than simply subtracting the percentage is essential; otherwise the result is slightly overstated.