GST Calculator India 2026
Calculate GST amount instantly — CGST + SGST for intra-state or IGST for interstate transactions. Supports exclusive and inclusive calculations.
Calculate GST
Enter the base price — GST will be added on top.
How GST Calculation Works
Exclusive GST (Adding GST)
Base Amount = ₹10,000
GST Rate = 18%
GST Amount = 10,000 × 18% = ₹1,800
Total = ₹11,800
Inclusive GST (Extracting GST)
Inclusive Amount = ₹11,800
GST Rate = 18%
Base = 11,800 ÷ 1.18 = ₹10,000
GST = ₹1,800
Frequently Asked Questions
What is the difference between exclusive and inclusive GST?
Exclusive GST: GST is added on top of the base amount (most B2B invoices). Inclusive GST: GST is already baked into the price — the calculator extracts the base amount and GST component. MRP prices on retail products are typically GST-inclusive.
What is CGST and SGST?
For intra-state sales (buyer and seller in the same state), GST splits into CGST (Central GST) and SGST (State GST). Both are exactly half of the total GST rate. E.g., on 18% GST: CGST = 9%, SGST = 9%.
When is IGST applicable?
IGST (Integrated GST) applies to interstate sales (buyer and seller in different states), imports and exports. The full GST rate is charged as IGST — no split.
Do I need to register for GST?
GST registration is mandatory if your turnover exceeds ₹40 lakh/year (goods) or ₹20 lakh/year (services). E-commerce sellers, importers/exporters, and all businesses making interstate supplies must register regardless of turnover.
How often must I file GST returns?
Under regular GST: GSTR-1 (monthly/quarterly) + GSTR-3B (monthly). Under QRMP scheme (turnover below ₹5 crore): quarterly returns with monthly tax payment. GSTR-9 (annual return) by December 31 every year.
Can I claim Input Tax Credit on purchases?
Yes — registered GST taxpayers can claim ITC on inputs used for business purposes, provided the vendor has filed their GSTR-1 and the invoice appears in your GSTR-2B.
What happens if I file GST returns late?
Late GSTR-3B: ₹50/day (₹25 CGST + ₹25 SGST). Late GSTR-1: ₹50/day. Interest on delayed payment: 18% p.a. Penalty: up to 10% of tax or ₹10,000 minimum.
Is GST applicable on exports?
Exports are zero-rated under GST — the GST rate is 0% and exporters can claim refund of ITC paid on inputs. You can either export without payment of GST (with LUT/Bond) or pay IGST and claim refund.