GST Calculator — Calculate GST Amount Online for Free
Calculate GST amount for any product or service
The GST Calculator helps businesses, freelancers, and consumers instantly calculate the Goods and Services Tax for any product or service. Whether you need to find GST on an exclusive price or extract GST from an inclusive amount, this tool handles all GST slabs — 5%, 12%, 18%, and 28%.
1Understanding GST Slabs in India
India's GST structure has four main rate slabs: 5% (essential goods — unbranded food, economy hotels, transport), 12% (processed food, computers, medicines), 18% (most services including restaurants, telecom, IT services, FMCG), and 28% (luxury goods, cars, tobacco, aerated drinks). Some items like unprocessed food grains, fresh vegetables, and educational services are exempt (0% GST). A few items like gold and silver carry 3% GST.
2GST Exclusive vs GST Inclusive — What's the Difference?
GST Exclusive means the stated price does NOT include GST, and GST is added on top. This is common in B2B transactions. For example, if a service costs ₹1,000 exclusive of 18% GST, the total invoice amount is ₹1,180. GST Inclusive means the stated price ALREADY includes GST. In this case, the base price is back-calculated: Base = Total × 100 / (100 + GST%). For ₹1,180 inclusive of 18% GST, the base price is ₹1,000.
3CGST, SGST, and IGST — How GST Is Split
For intra-state transactions, GST is split equally into CGST (Central GST) and SGST (State GST). For 18% GST, it becomes 9% CGST + 9% SGST. For inter-state transactions, IGST (Integrated GST) applies at the full rate — 18% IGST instead of 9+9. This matters for invoicing: intra-state invoices must show CGST and SGST separately, while inter-state invoices show IGST.
4GST Input Tax Credit (ITC)
Businesses registered under GST can claim Input Tax Credit — the GST paid on purchases can be offset against GST collected on sales, reducing the net GST liability. This eliminates the cascading tax effect. ITC is available only on business purchases, not personal expenses. Proper GST-compliant invoices from registered suppliers are required to claim ITC.
Frequently Asked Questions
Businesses with annual turnover above ₹40 lakh (₹20 lakh for service providers, ₹10 lakh in special category states) must register for GST. E-commerce sellers and inter-state suppliers must register regardless of turnover.