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Tool

GST Calculator.

Add GST to a base price, or pull the GST out of a tax-inclusive amount. Works for any rate and splits the tax into CGST + SGST for a local sale or IGST for an inter-state one.

Calculation

Since the Sept 2025 rate reform most goods and services sit at 5% or 18%; 40% applies to a short list of luxury and “sin” items, 3% to gold and 0.25% to rough diamonds. Check a specific item in the Rate Finder.

Type of supply

Intra-state = buyer and seller in the same state/UT. Inter-state = different states, or an import/export.

Result

Base amount (excl. GST)

Total amount (incl. GST)

How it works

  • Add GST: GST = amount × rate ÷ 100. Total = amount + GST.
  • Remove GST: base = amount × 100 ÷ (100 + rate). GST = amount − base.
  • Intra-state splits the GST in half: CGST and SGST (or UTGST in a union territory) at half the rate each.
  • Inter-state is charged as a single IGST at the full rate.

This is a straight arithmetic calculation and does not account for cess, MRP-inclusive pricing rules, composition-scheme rates, TCS, or rounding conventions on a tax invoice. Confirm the rate for your exact good or service on the GST portal.