GST Calculator India 2025 — Calculate GST on Any Amount

Whether you're a business owner, freelancer, or consumer, knowing how to calculate GST quickly is essential. This guide covers the exact formulas and a free online tool.

GST Slabs in India (2025)

| GST Rate | Category Examples | |---|---| | 0% | Essential food items (rice, wheat, vegetables), books, newspapers | | 5% | Packaged food, medicine, transport tickets, small restaurants | | 12% | Fruit juices, notebooks, umbrellas, non-AC hotels | | 18% | Most services (IT, consultancy), AC restaurants, household appliances, mobile phones | | 28% | Luxury goods, cars, cigarettes, aerated drinks, casinos |

How to Calculate GST — The Formula

Adding GST to a Price (Exclusive GST)

When you know the price excluding GST and want to find the total:

GST Amount = Original Price × (GST% / 100)
Final Price = Original Price + GST Amount

Example: Product price = ₹10,000, GST = 18%

GST Amount = 10,000 × (18/100) = ₹1,800
Final Price = 10,000 + 1,800 = ₹11,800

Removing GST from MRP (Inclusive GST)

When you know the MRP (price including GST) and want the original price:

Original Price = MRP / (1 + GST%/100)
GST Amount = MRP - Original Price

Example: Product MRP = ₹11,800, GST = 18%

Original Price = 11,800 / (1 + 18/100) = 11,800 / 1.18 = ₹10,000
GST Amount = 11,800 - 10,000 = ₹1,800

GST Calculator for Common Scenarios

Freelancer/Consultant Invoice (18% GST)

| Item | Amount | |---|---| | Service fee | ₹50,000 | | GST @ 18% | ₹9,000 | | Total Invoice Amount | ₹59,000 |

For intra-state billing: CGST = ₹4,500 + SGST = ₹4,500
For inter-state billing: IGST = ₹9,000

Shop Purchase (12% GST)

| Item | Amount | |---|---| | MRP (inclusive) | ₹5,600 | | Original price | ₹5,000 | | GST @ 12% | ₹600 |

Restaurant Bill (5% GST for non-AC)

| Item | Amount | |---|---| | Food total | ₹800 | | GST @ 5% | ₹40 | | Total Bill | ₹840 |

CGST and SGST Split

For intra-state transactions, GST is split equally between Centre and State:

| GST Rate | CGST | SGST | |---|---|---| | 5% | 2.5% | 2.5% | | 12% | 6% | 6% | | 18% | 9% | 9% | | 28% | 14% | 14% |

For inter-state: IGST = full GST rate (no split)

Quick GST Reference Table

18% GST (Most Common — IT Services, Restaurants)

| Amount (excl. GST) | GST @ 18% | Total | |---|---|---| | ₹1,000 | ₹180 | ₹1,180 | | ₹5,000 | ₹900 | ₹5,900 | | ₹10,000 | ₹1,800 | ₹11,800 | | ₹25,000 | ₹4,500 | ₹29,500 | | ₹50,000 | ₹9,000 | ₹59,000 | | ₹1,00,000 | ₹18,000 | ₹1,18,000 |

5% GST (Food, Medicine)

| Amount (excl. GST) | GST @ 5% | Total | |---|---|---| | ₹500 | ₹25 | ₹525 | | ₹1,000 | ₹50 | ₹1,050 | | ₹5,000 | ₹250 | ₹5,250 | | ₹10,000 | ₹500 | ₹10,500 |

Common GST Calculation Mistakes

❌ Applying GST to GST — GST is on base price, not on the GST amount itself
❌ Wrong slab — Check the exact HSN/SAC code; don't guess
❌ Missing CGST/SGST split — For intra-state, must show both components separately
❌ Calculating 28% as 14+14 — Correct. But show them on invoice separately
❌ Not mentioning Place of Supply — Determines CGST+SGST vs IGST

GST on Common Freelance Services

| Service | HSN/SAC | GST Rate | |---|---|---| | Software development | 998314 | 18% | | Web design | 998313 | 18% | | Consulting/Advisory | 999299 | 18% | | Content writing | 998912 | 18% | | Photography | 999212 | 18% | | Accounting services | 998222 | 18% | | Education/Training | 999293 | 18% |

Almost all services in India attract 18% GST.

Free GST Calculator Tool

Stop calculating manually. Use PaperFlow's free GST Calculator:

• Enter any amount
• Select GST rate (5%, 12%, 18%, or 28%)
• Instantly get: GST amount, CGST, SGST, IGST, and final total
• Works on mobile

No signup. No ads. Completely free.

Calculate GST instantly — free online tool, no signup required.