Calculate GST instantly for any amount and slab. Adds GST to a base price and removes GST from an inclusive price, with the CGST + SGST breakdown Indian businesses need.
Since the GST 2.0 reform of 22 September 2025, India runs two main slabs — 5% and 18% — plus 0% for exempt goods and a 40% rate for sin and luxury items. The old 12% and 28% slabs were withdrawn, and most of what a kirana sells moved down: biscuits, namkeen, noodles, soap, shampoo, toothpaste, hair oil, ghee and butter are now 5%. Detergent and cosmetics stayed at 18%; tobacco and aerated drinks sit at 40%.
For intra-state sales the tax splits equally into CGST and SGST (an 18% item is billed as 9% + 9%); inter-state sales are billed as a single IGST at the full rate. This calculator adds GST to a base price or extracts it from an inclusive price — the extraction direction is what most people get wrong on purchase invoices.
A distributor bills a kirana ₹10,000 (ex-GST) of detergent at 18%: GST = ₹1,800 (CGST ₹900 + SGST ₹900), invoice total ₹11,800. The retailer claims the ₹1,800 as input tax credit when filing GSTR-3B.
Divide the inclusive amount by (1 + rate). For ₹1,180 at 18%: 1180 ÷ 1.18 = ₹1,000 base, ₹180 GST. Subtracting 18% of the inclusive price is wrong — it overstates the tax.
Same state as the buyer → CGST + SGST, each at half the rate. Different state → one IGST line at the full rate. The total tax is identical either way; only the split changes.
On the taxable value after trade discounts shown on the invoice. Post-sale discounts via credit note follow different rules under Section 15(3) — reflect discounts on the invoice itself where possible.
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