GST Calculator
Add or remove GST in seconds. Supports 5%, 12%, 18% and 28% slabs with an automatic CGST/SGST split. Free and instant.
For inter-state sales, the total GST is charged as a single IGST instead of the CGST + SGST split shown above.
How GST is Calculated
GST (Goods and Services Tax) in India is charged at four main slabs — 5%, 12%, 18% and 28%. To add GST, multiply the base amount by the rate and add it back. To remove GST from a price that already includes it (a reverse GST calculation), divide the total by 1 plus the rate.
- Add GST: GST = amount × rate ÷ 100; Total = amount + GST
- Remove GST: Base = total ÷ (1 + rate ÷ 100); GST = total − base
- CGST/SGST: for intra-state sales, each is half of the total GST
GST Calculator — FAQ
How do I calculate GST on an amount?
To add GST, multiply the base amount by the GST rate and add it back: GST amount = amount × rate ÷ 100. For example, ₹1,000 at 18% GST adds ₹180, for a total of ₹1,180.
How do I remove GST from a total (reverse GST)?
Divide the GST-inclusive total by (1 + rate ÷ 100) to get the base amount. For ₹1,180 at 18%, the base is ₹1,180 ÷ 1.18 = ₹1,000 and the GST is ₹180.
What is the CGST and SGST split?
For intra-state sales, GST is split equally into CGST and SGST — each is half of the total GST. For inter-state sales it is charged as a single IGST at the full rate.
Which GST rates does this calculator support?
It supports the standard Indian slabs of 5%, 12%, 18% and 28%, and you can enter any custom rate as well.