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Tax 2026-07-13 10 min CalcBit Editorial Team

How to Calculate GST in India: Complete Guide with Examples for All Slabs

Learn how to calculate GST for all Indian tax slabs (5%, 12%, 18%, 28%). Includes formula, examples, exclusive vs inclusive calculations, and CGST/SGST/IGST breakdown.

Goods and Services Tax (GST) is a comprehensive indirect tax levied on the supply of goods and services in India. Understanding how to calculate GST correctly is essential for businesses, accountants, and consumers.

GST Formula

GST Exclusive (GST added to base price):

  • GST Amount = Base Price × GST Rate / 100
  • Total Price = Base Price + GST Amount

GST Inclusive (GST included in total price):

  • GST Amount = Total Price - (Total Price × 100 / (100 + GST Rate))
  • Base Price = Total Price × 100 / (100 + GST Rate)

GST Slabs in India

Example Calculations

### 18% GST Exclusive

Base Price: ₹10,000

GST Amount: ₹10,000 × 18/100 = ₹1,800

Total Price: ₹10,000 + ₹1,800 = ₹11,800

CGST (9%) + SGST (9%): ₹900 + ₹900 = ₹1,800

### 18% GST Inclusive

Total Price: ₹11,800

Base Price: ₹11,800 × 100/118 = ₹10,000

GST Amount: ₹11,800 - ₹10,000 = ₹1,800

### 5% GST Exclusive

Base Price: ₹5,000

GST Amount: ₹5,000 × 5/100 = ₹250

Total Price: ₹5,250

CGST (2.5%) + SGST (2.5%): ₹125 + ₹125 = ₹250

### 28% GST Exclusive

Base Price: ₹50,000

GST Amount: ₹50,000 × 28/100 = ₹14,000

Total Price: ₹64,000

CGST (14%) + SGST (14%): ₹7,000 + ₹7,000 = ₹14,000

CGST, SGST, and IGST Explained

  • Intra-state (within same state): GST is split equally as CGST (Central) and SGST (State)
  • Inter-state (across states): Full GST is charged as IGST (Integrated)
  • For 18% intra-state: CGST = 9%, SGST = 9%
  • For 18% inter-state: IGST = 18%

How to Remove GST from Total

To find the base price and GST amount from a total:

1. Base Price = Total × 100 / (100 + GST Rate)

2. GST Amount = Total - Base Price

Example: ₹11,800 including 18% GST

Base: 11,800 × 100/118 = ₹10,000

GST: 11,800 - 10,000 = ₹1,800

Using Our GST Calculator

Our Free GST Calculator handles all these calculations instantly:

  • Works for all GST slabs (5%, 12%, 18%, 28%)
  • Shows CGST/SGST split
  • Supports both inclusive and exclusive modes
  • Free to use with no registration

For specific rate calculations: 5% GST, 12% GST, 18% GST, 28% GST.

Tags

GST calculationhow to calculate GSTGST formulaGST slabsCGST SGST IGST breakdown
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Written by

CalcBit Editorial Team