GST Calculator
Add GST to a pre-tax amount, or work backwards from a tax-inclusive price to find the base amount and GST paid. Supports all standard GST rate slabs.
How to use the GST Calculator
Choose whether to add GST to a pre-tax amount or remove GST from a tax-inclusive bill.
Enter the amount in rupees.
Select the GST slab — 5%, 12%, 18% or 28%.
Get the base amount, GST charged, and the CGST/SGST split instantly.
Frequently asked questions
How do I remove GST from a total?
Divide the inclusive amount by (1 + rate/100). For 18% GST: base = total ÷ 1.18, and GST = total − base.
What are CGST and SGST?
GST is split equally between the Centre (CGST) and the State (SGST/UTGST) for intra-state sales. An 18% GST bill shows 9% CGST + 9% SGST.
Which GST slab applies?
Common slabs are 5% (essential goods), 12% and 18% (most services and goods) and 28% (luxury items). Check your invoice for the exact rate.