You are currently viewing How to Calculate GST Online?

How to Calculate GST Online?


Last Updated on July 20, 2023 by Kanakkupillai

How to Calculate GST Online?

Goods and Services Tax (GST) is an indirect tax system implemented in India on July 1, 2017. It is a comprehensive tax levied on the supply of goods and services throughout the country. GST replaced multiple indirect taxes such as central excise duty, service tax, value-added tax (VAT), and others.

Key features of GST in India:

Dual Structure:

GST in India follows a dual structure, comprising of Central GST (CGST) levied by the central government and State GST (SGST) levied by the state governments. Both CGST and SGST are applicable on intra-state transactions.

Integrated GST (IGST):

IGST is applicable on inter-state transactions and imports. It is collected by the central government but shared between the center and the destination state.

Input Tax Credit (ITC):

Under GST, businesses can claim input tax credit on taxes paid for inputs used in the production or supply of goods and services. This allows for the elimination of cascading taxes and helps businesses reduce their tax liability.

Threshold Exemption:

Small businesses with an annual turnover below a specified threshold (currently ₹20 lakhs for most states and ₹40 lakhs for certain special category states) are exempt from GST registration.

Electronic Filing:

GST compliance involves electronic filing of returns and other documents through the Goods and Services Tax Network (GSTN) portal. It simplifies the process and enables greater transparency.

Composition Scheme:

The composition scheme is available for small businesses with an annual turnover below a specified limit (currently ₹1.5 crore). It allows them to pay a lower rate of tax and reduces compliance requirements.

Importance of accurate GST calculation

GST calculator is of utmost importance in India due to the following reasons:


GST is a self-assessed tax system, where taxpayers are responsible for calculating and reporting their tax liability. Accurate GST calculation ensures compliance with the law, avoiding penalties, fines, or legal consequences resulting from incorrect reporting.

Input Tax Credit (ITC):

Accurate GST calculation enables businesses to claim the correct amount of ITC. ITC allows businesses to offset the taxes paid on inputs against the taxes collected on outputs, reducing their overall tax liability. Any errors in GST calculation can lead to incorrect ITC claims, resulting in financial losses for businesses.

Compliance Rating:

The GST system in India assigns a compliance rating to businesses based on their adherence to tax rules and regulations.

Avoidance of Penalties:

In case of non-compliance or incorrect GST calculation, businesses may face penalties and fines imposed by the tax authorities. Accurate GST calculation helps avoid such penalties, which can be substantial and impact the financial health of businesses.

Understanding GST

Different GST rates and categories

In India, Goods and Services Tax (GST) is levied on goods and services under different tax rates and categories. Here are the main GST rates and categories in India as of my knowledge cutoff in September 2021. Please note that these rates are subject to change, and it’s always advisable to refer to the latest official updates:

  • Standard Rate (CGST/SGST):
  1. 5%: Applies to essential goods such as certain food items, books, healthcare services, transportation services, etc.
  2. 12%: Applies to goods like processed food, computers, smartphones, industrial intermediaries, etc.
  3. 18%: Applies to goods like electrical products, mineral water, hotels with room tariffs between INR 1,000 and INR 7,500, etc.
  4. 28%: Applies to goods like luxury items, automobiles, tobacco products, aerated drinks, etc.
  • Lower Rates:
  1. 25%: Applies to rough precious and semi-precious stones.
  2. 3%: Applies to gold and other precious metals.
  3. 5%: Applies to packaged cement.
  4. 12%/18%: Applies to certain items like fertilizers, air travel, etc.
  • Nil Rate:

Certain essential goods and services are exempt from GST, such as fresh fruits and vegetables, unprocessed grains, milk, education services, healthcare services, etc.

  • Compensation Cess:

Apart from the GST rates mentioned above, some specific goods attract additional compensation cess. These include luxury cars, tobacco products, aerated drinks, and coal.

HSN and SAC codes

Under Goods and Services Tax (GST) in India, businesses use Harmonized System of Nomenclature (HSN) codes and Services Accounting Code (SAC) for proper classification and identification of goods and services. Here is a brief explanation of HSN codes and SAC codes:

  • HSN Codes:

HSN codes are used to classify goods and products for taxation purposes. The codes are globally recognized and facilitate uniformity in the classification of goods. HSN codes are numerical codes assigned to specific goods based on their nature, composition, or function. The first two digits represent the chapter, followed by two more digits for the headings, and further digits for sub-headings.

  • SAC Codes:

SAC codes are used for the classification of services under GST. They help in the systematic categorization of various services for tax purposes. SAC codes are numerical codes consisting of six digits. Each digit signifies a specific aspect of the service. The first two digits represent the major service category, followed by two digits for the main service sub-category, and the final two digits for the detailed service classification. For example, SAC code 998712 pertains to management consulting services. Businesses must mention the relevant SAC code for services rendered while filing GST returns.

Steps to Calculate GST Online

Step 1: Determine the transaction type

To calculate GST online, the first step is to determine the transaction type, whether it is an intra-state transaction (within the same state) or an inter-state transaction (between different states). This distinction is crucial as it affects the application of CGST, SGST, or IGST and determines the tax rate and the appropriate tax liability.

Step 2: Identify the applicable GST rate

To calculate GST online, the applicable GST rate for the specific goods or services needs to be determined. This can be done by referring to the official GST rate schedule or using GST rate finder tools provided by the government. Once the applicable rate is determined, it can be used to calculate the GST amount.

Step 3: Gather necessary information

To calculate GST online, gather the following information:

  • invoice value,
  • type of transaction (intra-state or inter-state),
  • applicable tax rates based on the goods or services,
  • input tax credit details, and
  • any additional cess or exemptions.

Use an online GST calculator or accounting software to input the information and obtain the GST calculation results.

Step 4: Perform GST calculation

To perform GST calculation online, follow these steps:

  1. Determine the applicable GST rate for the goods or services.
  2. Calculate the taxable amount by subtracting any discounts or exemptions from the total invoice value.
  3. Multiply the taxable amount by the GST rate.
  4. Add the calculated GST amount to the taxable amount to obtain the total amount payable.
  5. Double-check your calculations for accuracy.

Step 5: Verify and cross-check the calculation

Verification and cross-checking are essential steps while calculating GST online. Ensure accurate input of transaction values, tax rates, and appropriate HSN/SAC codes. Reconcile calculations with the GST tax rates to determine the correct tax liability. Regularly review and validate calculations to avoid errors and maintain compliance.

Using an Online GST Calculator

Online GST calculators in India are tools that help businesses and individuals calculate Goods and Services Tax (GST) liabilities quickly and accurately. These calculators are available on various websites and provide a user-friendly interface to input transaction values, tax rates, and other necessary details. They automatically calculate the GST amount, including integrated, central, and state taxes, based on the provided inputs.

Advantages of using online calculators

There are several advantages to using online GST calculators in India:

  1. Accuracy: Online calculators perform calculations automatically, reducing the risk of manual errors and ensuring accurate GST calculations.
  2. Convenience: Online calculators are easily accessible anytime, anywhere, through internet-enabled devices, offering convenience to businesses and individuals.
  3. Updated rates: Online calculators are regularly updated with the latest GST rates, ensuring compliance with current tax regulations.
  4. Cost-effective: Using free online calculators eliminates the need for purchasing dedicated software, making it a cost-effective solution for businesses of all sizes.
  5. User-friendly interface: Online calculators have intuitive interfaces, making them user-friendly, even for individuals without advanced tax knowledge.

Choosing a reliable GST calculator

When selecting a reliable GST calculator in India, consider the following factors:


Choose a calculator that is known for its accurate calculations and up-to-date tax rates.

User-friendly Interface:

Look for a calculator with an intuitive interface that is easy to navigate and use.


Ensure that the calculator platform is secure and protects sensitive data.

Reputation and Reviews:

Check user reviews and ratings to gauge the reliability and performance of the calculator.

Additional Features:

Consider calculators that offer extra functionalities like invoice generation, tax rate history, or ITC calculation.

Regular Updates:

Choose a calculator that stays updated with the latest GST regulations and changes.


Calculating GST online using reliable calculators offers accuracy, convenience, and time-saving benefits. It ensures compliance with tax regulations, enables efficient financial planning, and simplifies the process for businesses and individuals in India.

Kanakkupillai provides our clientwith an online GST calculator assuring:

  • Accuracy
  • User-friendly Interface
  • Security
  • Reputation and Reviews
  • Additional Features
  • Regular Updates.

Click here Kanakkupillai!!


Kanakkupillai is your reliable partner for every step of your business journey in India. We offer reasonable and expert assistance to ensure legal compliance, covering business registration, tax compliance, accounting and bookkeeping, and intellectual property protection. Let us help you navigate the complex legal and regulatory requirements so you can focus on growing your business. Contact us today to learn more.