Tax & Business · India

GST Calculator

Add GST to a pre tax amount or extract GST from an inclusive amount. Free Indian GST calculator with CGST plus SGST and IGST split for any rate.

Goods and Services Tax, or GST, is the indirect tax that replaced VAT, service tax and a slew of other levies in 2017. It applies to almost every transaction in India at one of seven rates (0, 0.1, 3, 5, 12, 18 and 28 percent). The GST calculator on this page handles two common needs: adding GST to a pre tax amount (the exclusive case), and extracting GST from an inclusive amount (the reverse case). It also splits the tax into CGST plus SGST for intra state supplies or IGST for inter state supplies.

GST

Base amount
₹10,000
GST
₹1,800
18% of base
Total amount
₹11,800

Tax split

CGST (9%)₹900
SGST (9%)₹900

Why use the GST Calculator

GST is everywhere in business invoicing, customer billing and personal record keeping. The two most common errors are using the inclusive formula when the amount is actually exclusive (overcharging), and forgetting to split into CGST plus SGST when the supply is within the same state (which affects input tax credit eligibility). The calculator handles both directions and the split automatically, so the maths is correct without spreadsheet gymnastics.

Benefits at a glance

  • Both add and remove GST

    Toggle between exclusive (add GST to a pre tax amount) and inclusive (extract GST from a final price). The same calculator handles both directions accurately.

  • All seven GST rates supported

    0 percent, 0.1 percent (specified exports), 3 percent (gold), 5 percent, 12 percent, 18 percent and 28 percent. Pick the rate applicable to your goods or service.

  • CGST plus SGST or IGST split

    Intra state supplies split GST equally into Central GST and State GST. Inter state supplies levy a single Integrated GST. The calculator shows the split based on your selection.

  • Useful for invoicing and reverse calculations

    Quickly compute the GST component of an MRP inclusive price, or generate the tax line for a B2B invoice. The numbers are precise to the rupee.

How to use the GST Calculator

  1. 1

    Choose exclusive or inclusive mode

    Exclusive if the amount is pre tax and you need to add GST. Inclusive if the amount already includes GST and you need to find the base and tax separately.

  2. 2

    Enter the amount

    The pre tax amount in exclusive mode, or the inclusive amount in inclusive mode. The calculator does the right computation based on your mode selection.

  3. 3

    Pick the GST rate

    Select the applicable rate. Most services and goods are 18 percent. Essentials are at lower rates (5 or 12 percent). Luxury and sin goods are at 28 percent.

  4. 4

    Tick intra state or inter state

    Intra state for supplies within the same state (CGST plus SGST split). Inter state for supplies across state borders (IGST). The total tax amount is the same; only the split differs.

  5. 5

    Read base, GST and total

    The calculator shows the base amount, the GST amount and the total. The split table shows CGST and SGST for intra state, or IGST for inter state.

Frequently asked questions

What is the difference between CGST, SGST and IGST?

For intra state supplies (where the buyer and seller are in the same state), GST is split equally between Central GST (collected by the central government) and State GST (collected by the state government). For inter state supplies (across state borders), the same total GST is levied as Integrated GST and collected by the central government, which then settles with the destination state. The total tax burden is identical; only the split differs.

What are the common GST rates in India?

Zero percent for essentials including unbranded food grains, fresh vegetables and milk. 0.1 percent for specified exports. 3 percent for gold and precious stones. 5 percent for many essentials including transport. 12 percent for processed food, basic mobile services and several intermediate goods. 18 percent is the standard rate for most services and goods. 28 percent for luxury, sin goods including tobacco, aerated drinks and high end automobiles.

How do I extract GST from an MRP inclusive price?

Use the inclusive mode in the calculator. If a product costs 1,180 inclusive of 18 percent GST, the base price is 1,180 divided by 1.18 which equals 1,000. The GST component is 1,180 minus 1,000 which equals 180. The calculator does this division automatically.

What is reverse GST calculation?

Reverse GST means computing the base amount and GST separately when only the inclusive amount is known. The formula is base equals inclusive divided by (1 plus rate). The GST component is inclusive minus base. Useful when the supplier provides only the final price and you need the tax breakdown for accounting or input tax credit.

When is IGST applicable instead of CGST plus SGST?

IGST applies when the place of supply is different from the location of the supplier. For physical goods, this typically means the buyer is in a different state from the seller. For services, the rules depend on the nature of the service and the location of the recipient. The total tax is the same, but the split affects input tax credit utilisation rules in the GST returns.

Can I claim input tax credit on the GST I pay?

Yes, if you are GST registered and the input is used for taxable business supplies. The credit can be used to offset your output GST liability. Input tax credit rules differ for CGST, SGST and IGST: CGST credit can offset CGST and IGST output, SGST credit can offset SGST and IGST output, IGST credit can offset all three. The calculator does not handle input tax credit utilisation; that is a returns level computation.

Is GST applicable on every transaction?

GST applies to almost all supply of goods and services in India, with specific exemptions for items in the 0 percent list and certain non taxable transactions like interest income, dividends and some agricultural produce. Small businesses with turnover below the threshold (40 lakh for most states, 20 lakh for service businesses) are exempt from GST registration but cannot claim input tax credit.

Final word

The GST calculator handles the routine but error prone arithmetic of adding or removing GST and splitting it correctly across central and state levies. Use it for personal record keeping when checking a bill, for invoicing when generating a quote and for reverse calculation when only an inclusive price is on hand. The numbers are simple but the consequences of getting them wrong (especially around CGST plus SGST versus IGST) flow through to GST returns, so doing them right matters.

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