India GST Calculator — CGST, SGST & IGST Split

Free India GST calculator built on the 2026 rate structure: 5% merit rate, 18% standard rate, 40% demerit rate, plus the 3% and 0.25% special rates. It does what a generic tax calculator cannot — it splits the tax by head: CGST + SGST for a supply within one state, a single IGST line across states, and UTGST where a union territory levies it. Add GST to a taxable value or extract it from a GST-inclusive total.

How to use this calculator

Step 1. Enter the amount — the taxable value, or the GST-inclusive total to work backwards.

Step 2. Pick the slab: 5% or 18% for most supplies, 40% for demerit goods, 3% for gold and silver.

Step 3. Choose the direction: intra-state (CGST + SGST) or inter-state (IGST).

Step 4. Read the taxable value, each tax head with its amount, and the invoice total.

Key figures and context

• Intra-state: the slab halves into equal CGST and SGST — 18% prints as 9% + 9%
• Inter-state: one IGST line at the full rate; exports and SEZ supplies are zero-rated IGST
• The split follows the place of supply, not the buyer's registered address
• Since 22 Sept 2025 the slabs are 0%, 5%, 18% and 40% — the 12% and 28% slabs were abolished
• Same engine as the Xuvilo invoice generator's GST mode, so the split matches the document

Open the free India GST Calculator now, or browse the full business calculator suite.