GST Calculator
Calculate Goods and Services Tax (GST) either way — add GST on top of a base amount, or work out how much GST is already included in a total. Get an instant CGST and SGST breakdown for any GST rate from 0% to 28%.
Fill in the form and select "Calculate" to see your results here.
What is the GST Calculator?
Goods and Services Tax (GST) is India's single indirect tax on the supply of goods and services, replacing older taxes such as VAT, service tax and excise duty. GST is charged as a percentage of the value of a supply, and is structured in slabs — most goods and services fall under 5%, 12%, 18% or 28%, depending on the item. This calculator works in both directions: you can add GST to a base amount to see the total a customer pays, or start from a GST-inclusive total and work backward to see how much of it is the base price and how much is tax.
How to use this calculator
- Choose a calculation mode — "Add GST to Amount" if you have a base price and want the GST-inclusive total, or "Remove GST from Amount" if you already have a total and want to know the base price and tax within it.
- Enter the amount. In exclusive mode this is the amount before GST; in inclusive mode this is the total amount including GST.
- Enter the applicable GST rate — commonly 5%, 12%, 18% or 28%.
- Select "Calculate GST" to see the base amount, the GST amount split into CGST and SGST, and the total amount.
Formula
In both modes, the GST amount is then split equally into CGST and SGST, assuming the supply is within the same state. See the editorial policy for how calculation methods on this site are verified.
Example
Suppose a product has a base price of ₹10,000 and attracts 18% GST. In exclusive mode, the GST amount works out to ₹1,800 (₹900 CGST + ₹900 SGST), so the customer pays a total of ₹11,800. Now look at the same transaction from the buyer's side: if the buyer only knows the final invoice total of ₹11,800 and the 18% GST rate, switching to inclusive mode and entering ₹11,800 as the amount recovers the same figures — a base amount of ₹10,000 and a GST amount of ₹1,800. Both modes describe the same transaction from opposite directions.
Factors that affect the result
- CGST, SGST and IGST. This calculator assumes an intra-state supply, where the total GST is split equally between CGST (central) and SGST (state). For an inter-state supply, the full GST amount is instead charged as IGST — a single tax with no equal split — which this calculator does not model.
- GST rate slab. The rate you enter should match the slab applicable to your specific goods or service. Using the wrong slab will produce a technically correct calculation for the wrong rate.
- Exemptions and special rates. Certain goods and services are GST-exempt or taxed at rates outside the standard slabs (e.g. 0.25%, 3%, or cess-inclusive rates on select items). This calculator only performs flat-rate percentage math and does not know about item-specific exemptions.
- Compensation cess. Certain goods (such as tobacco, aerated drinks and some automobiles) attract an additional compensation cess on top of GST, which this calculator does not include.
- Reverse charge mechanism. In specific cases the recipient, not the supplier, is liable to pay GST directly to the government. This calculator does not model reverse charge scenarios.
Frequently Asked Questions
Goods and services in India are commonly taxed at 5%, 12%, 18% or 28%, depending on the category. Some items are exempt or taxed at special rates outside this list. This calculator lets you enter any rate from 0% to 28%, so you can use it for whichever slab applies to your transaction.
For a supply within the same state (intra-state), the total GST is split equally between CGST (collected by the central government) and SGST (collected by the state government) — this is what this calculator assumes. For a supply between two different states (inter-state), IGST applies instead, and the full GST amount is collected by the central government and later apportioned to the destination state.
Select "Remove GST from Amount (Inclusive)" as the calculation mode, enter the total price you already have, and enter the applicable GST rate. The calculator divides the total by (1 + GST rate / 100) to work out the base amount, then shows the GST portion separately.
No. This is a general-purpose GST calculator based on a flat rate you enter. It does not apply item-specific exemptions, the compensation cess charged on certain goods, or reverse charge mechanism rules — check the applicable notification for your specific goods or services if these apply to you.
Use CGST/SGST (shown by this calculator) if the supplier and the place of supply are in the same state. Use IGST — the full GST amount, not split — if the supply crosses state lines. This calculator only models the intra-state (CGST/SGST) case.
Related calculators
Tax calculations are estimates based on the information entered. They do not account for every exemption, cess, or edge case in GST law, and are not a substitute for professional tax advice. See our full disclaimer.