GST Calculator

Since 22 September 2025, when the GST Council’s "GST 2.0" reform took effect, there are two main slabs — 5% and 18% — plus 0% for exempt essentials and a 40% rate for luxury and sin goods such as tobacco, pan masala and high-end cars. Special rates of 0.25% (rough diamonds) and 3% (gold, silver, jewellery) continue. The 12% and 28% slabs were abolished: most 12% items moved to 5% and most 28% items to 18%.

Divide by one plus the rate. A ₹1,180 price that includes 18% GST has a taxable value of 1,180 ÷ 1.18 = ₹1,000 and GST of ₹180. Taking 18% of ₹1,180 (₹212.40) is the common mistake; it overstates the tax because the percentage applies to the base, not the total.

They are the same tax collected by different governments. On a sale within one state the rate is split equally: an 18% sale carries 9% CGST to the Centre and 9% SGST to the state. On a sale from one state to another the whole 18% is IGST, collected by the Centre and shared with the destination state. Your invoice must show the right split, but the customer pays the same amount.

Only for supplies made before 22 September 2025. The calculator accepts them so old invoices can be checked, and labels them as abolished. For anything supplied after that date, look up the item’s new rate — the Council published item-wise schedules — rather than assuming it stayed where it was.

Yes, if the discount is shown on the invoice at the time of supply. Under section 15 of the CGST Act, a discount recorded on the invoice is excluded from the taxable value, so GST applies to the net price. Post-sale discounts are excluded only if they were agreed before the supply and linked to the invoice. Enter the discounted amount here.

It takes the tax out of a price that already includes it. Divide the inclusive price by (1 + rate) to get the base: ₹1,180 at 18% is ₹1,180 ÷ 1.18 = ₹1,000 base and ₹180 GST. The common mistake is to take 18% of ₹1,180, which gives ₹212.40 and overstates the tax. Choose “price includes GST” on this page and it applies the division, then splits the tax into CGST and SGST or into a single IGST line for an interstate supply.

It starts from the price the customer pays and works back to the base and the tax, instead of starting from the base and adding tax on. Pick the inclusive option here, enter ₹2,360 at 18%, and the base is ₹2,000 with ₹360 of GST; the exclusive option would add 18% to ₹2,000 to reach the same ₹2,360. Both directions split the tax into CGST and SGST for a sale within a state, or show a single IGST line, which is all an IGST calculator is, for a sale across state lines.