GST Calculator – Add or Remove GST (5%, 18%, 40%)
Add GST to a base price or back it out of an inclusive amount. Shows the CGST/SGST split for intra-state and IGST for inter-state supplies.
Indicative estimate. This result depends on government rates that are still pending verification against the official notification. Confirm the exact amount with the relevant department before paying.
- Base amount
- ₹10,000
- GST amount
- ₹1,800
- CGST
- ₹900
- SGST / UTGST
- ₹900
- IGST (inter-state)
- ₹1,800
Formula
Exclusive: GST = Amount × Rate ÷ 100. Inclusive: Base = Amount ÷ (1 + Rate ÷ 100), GST = Amount − Base. CGST = SGST = GST ÷ 2.
Worked example
₹10,000 + 18% GST = ₹11,800 (CGST ₹900 + SGST ₹900). ₹11,800 inclusive → base ₹10,000.
Assumptions
- Rates reflect the GST Council's September 2025 rationalisation; 12% and 28% kept for older invoices.
Frequently asked questions
- When is IGST charged instead of CGST + SGST?
- IGST applies when the supplier and buyer are in different states. Within a state, GST is split equally into CGST and SGST.
- What are the GST rates in 2026?
- The main slabs are 5% and 18%, with 40% on luxury and sin goods, 3% on gold and 0.25% on rough diamonds. Many items moved from 12% and 28% in September 2025.
Rules used: GST rate slabs. Last reviewed 2026-10-31.
These rates are pending verification against official sources. Confirm with the relevant department before relying on the figure.
- Since 22 September 2025 the main GST slabs are 5% and 18%, with 40% on select sin and luxury goods. 12% and 28% remain here for older invoices.
Last reviewed 2026-10-31. Results are estimates for information only and do not constitute financial, tax or legal advice.