GST Calculator – Calculate Your GST Amount through GST Formula

| Updated on: August 24, 2021

What is GST?

GST is an Indirect Tax which has replaced many Indirect Taxes in India. The Goods and Service Tax Act was passed in the Parliament on 29th March 2017. The Act came into effect on 1st July 2017; Goods & Services Tax Law in India is a comprehensive, multi-stage, destination-based tax that is levied on every value addition.

In simple words, Goods and Service Tax (GST) is an indirect tax levied on the supply of goods and services. This law has replaced many indirect tax laws that previously existed in India.

What are the 3 types of GST Collected by Government

There are currently three types of GST

  • CGST – Central GST – Applies to sales within the state – goes to Central Government
  • SGST – State GST – Applies to sales within the state – goes to State Government
  • IGST – Integrated GST – Applies to sales outside the state – goes to Central Government

For example, if you sell something within the state, 50% of the GST will be CGST and 50% of the GST will be SGST. But when you sell something outside a state, 100% of it will be IGST which will go to the Central Government.

Now that you have a basic understanding of how GST works, we can go ahead to understand the working of GST in Tally along with its accounting and calculation.

Advantages of GST Calculator

GST calculator helps bifurcate between the different tax slabs - CGST, SGST and IGST. With the help of a GST calculator, you will know which tax slab will your transaction fall under and how much of tax will be levied on the goods/services being sold/purchased. It also saves time and reduces the chances of human error while computing the total cost of goods and services.

What is GST Calculator?

Couple of years into the GST era, most businesses have become conversant with the basic information they need to be on top of, as far as their goods and services are concerned. The information is nothing but – the GST rates, HSN codes, SAC codes etc. which will help them to calculate GST faster, prepare GST compliant invoices faster and therefore, conduct businesses faster.

However, there are many scenarios, wherein a businessman may be faced with an amount excluding GST, or with an amount including GST. In the fast-paced business world, one needs to know the quickest method to determine both GST exclusive and GST inclusive prices, so as to make quick sales and purchase decisions. Most countries have found useful in these circumstances a GST calculator, India too will be no different. In fact with the right knowledge of the formula, one can create a GST tax calculator in excel and keep it handy. However, the first step to being able to maintain and use a GST calculator is to be familiar with the GST rates.

GST rates

GST rate schedule for goods

Under GST, there are 7 specified rates for goods, each of which have been classified under a Schedule in the GST Rates Booklet for Goods. They are as follows:

  • Schedule I: Nil Rated
  • Schedule II: 0.25%
  • Schedule III: 3%
  • Schedule IV: 5%
  • Schedule V: 12%
  • Schedule VI: 18%
  • Schedule VII: 28%

Under each Schedule, the full list of specified Goods has been provided under two columns – "Chapter/Heading/Sub-heading/Tariff item" which provides the information of the HSN Codes & "Description of Goods" which provides the unique description of the goods for the benefit of the business.

GST rate schedule for services

Under GST, there 5 specified rates for services, each of which have been classified in the GST Rates Booklet for Services. They are as follows:

  • Nil Rated
  • 5%
  • 12%
  • 18%
  • 28%

Formulae for GST calculation

GST calculation can be explained by simple illustration : If a goods or services is sold at Rs. 1,000 and the GST rate applicable is 18%, then the net price calculated will be = 1,000+ (1,000X(18/100)) = 1,000+180 = Rs. 1,180

Know how to calculate GST and use the right GST tax calculator here.

How to calculate GST using GST Formula?

Due to the simplification of the indirect taxation regime, the calculation of the applicable taxes has become much simpler. The GST rates applicable on the various goods or services can now be calculated, based on the nature of the transaction – inter-state or intra-state.

Intra-state GST tax calculator

In case of Intra-State transactions, GST can be calculated as follows:

  • CGST = Applicable GST Rate / 2 (for 28%, CGST will be 28/2=14%)
  • SGST / UTGST = Applicable GST Rate / 2 (for 28%, SGST will be 28/2=14%)

In other words, CGST + SGST / UTGST = Applicable GST Rate

Inter-State GST tax calculator

In case of Inter-State transactions, GST can be calculated as follows:

  • IGST = Applicable GST rate

Note: Wherever applicable, GST Compensation Cess should be added to the applicable GST rate for the correct tax calculations. Even a GST credit calculator, will be based on the same principles.

Thus, a simple formula arises:

  • GST Amount = (Original Cost*GST Rate Percentage) / 100
  • Net Price = Original Cost + GST Amount

Inclusive GST calculator

However, in those cases, where a price inclusive is mentioned, a reverse GST calculator will need to be applied. Like above, this also will be based on a simple formula:

  • GST Amount = GST Inclusive Price * GST Rate /(100 + GST Rate Percentage)
  • Original Cost =  GST Inclusive Price * 100/(100 + GST Rate Percentage)

Examples of GST Calculations with Formula

A simple example of how GST is calculated typically by business owners

Particulars Rate(%) Amount
Invoice value 12% 2,00,000
GST 12,000
Price to be charged on the Invoice 2,24,000

GST calculation by manufacturers:

Particulars Rate(%) Amount Pre-GST Amount under GST
Cost of the product 2,00,000 2,00,000
Profit 10.00% 20,000 20,000
Excise Duty 12.50% 27,500 Nil
Total 2,47,500 2,20,000
VAT 12.50% 30,938 Nil
CGST 6% Nil 13,200
SGST 6% Nil 13,200
Final Invoice to the wholesaler 2,78,438 2,46,400


  • What is GST Calculator?

GST calculator helps you find out either net or gross price of your product based on a percentage-based GST (Goods and Services Tax) rate. It's straightforward to use - provide values that you know (for example, net price and GST rate) to receive other values (in this case, gross price and tax amount)

  • What is GST inclusive amount?

GST inclusive amount refers to the total value of the product after including the GST amount in the original value of the product. The tax is not charged separately from the customer

  • What is GST exclusive amount?

GST Exclusive amount refers to the value of the product by subtracting the GST amount from the GST Inclusive value of the product.

  • What are the benefits of GST Calculator?

Here are some of the key benefits of using a GST calculator:

  • It helps users determine the net or gross product price on GST rates
  • It helps users differentiate between different GST types - SGST, CGST and IGST and calculate each tax accurately
  • It saves time by providing instant results
  • It lowers the risk of human error when calculating the cost of products and services
  • It is simple to use and helps you calculate GST in a hassle-free manner.
  • If dealer is migrated with incorrect PAN in the case, if the status of firm is changed from proprietorship to partnership?

Aggregate turnover does not include value of inward supplies on which tax is payable on reverse charge basis. What if the dealer migrated with wrong PAN as the status of firm was changed from proprietorship to partnership? New registration would be required as partnership firm would have new PAN.

Read More on GST

GST Software, GST Software for CAs, GST Software for Traders, GST Invoicing Software, GST on Freight, GST on Ecommerce, GST Impact on TCS, GST Impact on TDS, GST Exempted Goods & Services, Reverse Charge Mechanism in GST, GST Declaration

GST Rates & Charges

GST Rates, GST Rate Finder, GST Rate on Labour Charges, HSN Codes, SAC Codes, GST State Codes

Types of GST

CGST, SGST, IGST, UTGST, Difference between CGST, SGST & IGST

GST Returns

GST Returns, Types of GST Returns, New GST Returns & Forms, Sahaj GST Returns, Sugam GST Returns, GSTR 1, GSTR 2, GSTR 3B, GSTR 4, GSTR 5, GSTR 5A, GSTR 6, GSTR 7, GSTR 8, GSTR 9, GSTR 10, GSTR 11


Compliance solutions right from invoicing to filing returns to e-invoicing, are just a click away.