What is the mathematical formula to calculate GST

Understanding the Calculation of GST

Calculating the Goods and Services Tax (GST) on goods or services is straightforward with a simple mathematical formula. Here’s how you can determine the GST amount and the total cost inclusive of GST.

The GST Calculation Formula

The formula to calculate GST is:
[ \text{GST} = \left(\frac{\text{Price of goods or services} \times \text{GST rate}}{100}\right) ]

In this formula:

• Price of goods or services: The original cost of the item or service before GST.
• GST rate: The applicable GST percentage.

Example Calculations

Let’s walk through some examples to see how this formula works in practice.

Example 1: Calculating GST at 18%

Imagine you bought a product worth ₹100 and the GST rate is 18%.

1. Calculate the GST amount:
   [ \text{GST} = \left(\frac{₹100 \times 18}{100}\right) = ₹18 ]
2. Add the GST amount to the original price to get the total cost:
   [ \text{Total price} = ₹100 + ₹18 = ₹118 ]

Example 2: Calculating GST at 12%

Now, consider the same product priced at ₹100, but with a 12% GST rate.

1. Calculate the GST amount:
   [ \text{GST} = \left(\frac{₹100 \times 12}{100}\right) = ₹12 ]
2. Add the GST amount to the original price:
   [ \text{Total price} = ₹100 + ₹12 = ₹112 ]

Example 3: Calculating GST at 28%

Lastly, let’s use a 28% GST rate for the same product.

1. Calculate the GST amount:
   [ \text{GST} = \left(\frac{₹100 \times 28}{100}\right) = ₹28 ]
2. Add the GST amount to the original price:
   [ \text{Total price} = ₹100 + ₹28 = ₹128 ]

Applying the GST Formula to Other Rates

You can use the same formula to calculate GST for any rate. Simply substitute the Price of goods or services and the GST rate into the formula:
[ \text{GST} = \left(\frac{\text{Price of goods or services} \times \text{GST rate}}{100}\right) ]

This method ensures you accurately compute the GST amount and the final price, helping you manage your finances better. Whether you’re a consumer calculating the total cost of your purchase or a business owner determining the correct price to charge, this straightforward formula is invaluable for ensuring compliance and transparency in pricing.