The Goods and Services Tax (GST) is applied to almost every product and service sold in India. Whether you are a business owner creating invoices, a freelancer calculating your fees, or a consumer trying to understand what you are actually paying — knowing how to calculate GST correctly is essential.
What is GST and How Does It Work?
GST replaced multiple indirect taxes in India in July 2017. It is a destination-based tax collected at every stage of the supply chain. For most transactions within the same state, GST is split equally into CGST (Central GST) and SGST (State GST). For inter-state transactions, a single IGST (Integrated GST) is charged at the same combined rate.
GST Rate Slabs in India
0% applies to essential items including fresh fruits and vegetables, milk, eggs, and educational services. 5% applies to items like edible oils, domestic LPG, and economy class air travel. 12% applies to processed foods, mobile phones, and business class travel. 18% is the standard rate applying to most services, electronics, and restaurant food. 28% applies to luxury goods, cars, tobacco, and aerated beverages.
How to Add GST to a Price
Formula: GST Amount = Original Price × (GST Rate / 100). Total Price = Original Price + GST Amount. Example: A service costs ₹10,000 + 18% GST. GST = ₹10,000 × 0.18 = ₹1,800. Total = ₹11,800 (CGST ₹900 + SGST ₹900). Use the AILabForce GST Calculator to do this instantly for any amount and any rate.
How to Remove GST from a Price (Reverse Calculation)
When you have a GST-inclusive price and need to find the original pre-GST amount: Original Price = Inclusive Price ÷ (1 + GST Rate/100). Example: A product is priced at ₹11,800 including 18% GST. Original Price = ₹11,800 ÷ 1.18 = ₹10,000. GST Amount = ₹11,800 - ₹10,000 = ₹1,800. Use our Reverse GST Calculator to do this automatically.
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