Under India's GST system, an intra-state sale splits tax into CGST (collected by the Centre) and SGST (collected by the state), each at half the total rate. An inter-state sale instead attracts IGST at the full rate. This calculator shows both scenarios for a given amount.
How to Use This Calculator
- Enter the taxable amount.
- Choose the applicable GST rate.
- Select whether the sale is intra-state (CGST + SGST) or inter-state (IGST).
- View the resulting tax breakdown.
How the Calculation Works
Intra-state: CGST = SGST = (Amount × Rate/100) ÷ 2
Inter-state: IGST = Amount × Rate/100
Worked Example
On ₹20,000 at 18% GST, intra-state: CGST = ₹1,800, SGST = ₹1,800, total tax = ₹3,600. Inter-state: IGST = ₹3,600 — the total tax collected is identical, only the split changes.
Who Should Use This
Useful for accountants preparing GST invoices, and business owners who need to know which tax head to enter on a sales invoice depending on the buyer's location.
Important Considerations
Whether a sale is intra-state or inter-state depends on the location of supply, not just billing address in every case — special rules apply to certain services. When unsure, verify with a tax professional.
Common Mistakes
Charging both CGST/SGST and IGST, or splitting an inter-state sale into CGST/SGST, is a common invoicing error that this calculator helps avoid by making the two scenarios explicit.
References
Official rates: CBIC GST Portal.