GST Calculator
Add or remove GST in seconds. Enter an amount, pick a slab, and get the GST amount, the net and gross values, and the CGST + SGST or IGST split for intra-state and inter-state supplies.
How to calculate GST
GST is a percentage added to the value of goods or services. There are two common situations:
| Situation | Formula |
|---|---|
| Add GST (you have the net price) | GST = Net × Rate ÷ 100; Gross = Net + GST |
| Remove GST (you have the gross price) | Net = Gross × 100 ÷ (100 + Rate); GST = Gross − Net |
On an intra-state supply (within the same state), GST is split equally into CGST and SGST. On an inter-state supply (between states), the whole tax is IGST.
GST rate slabs
India’s main GST slabs are 5%, 12%, 18% and 28%, with a special 3% rate on gold and a 0% (exempt/nil) category for essentials. Most goods and services fall under 18%. Always confirm the exact rate and HSN/SAC code for your product before invoicing.
Worked example
Add 18% GST to a net amount of ₹10,000: GST = ₹1,800, so the gross invoice value is ₹11,800. For an intra-state sale this is CGST ₹900 + SGST ₹900; for an inter-state sale it is IGST ₹1,800. To work backwards from a ₹11,800 gross price, the net is ₹10,000 and the GST is ₹1,800.
Good to know
CGST + SGST = IGST
For the same rate, the total tax is identical whether intra-state (CGST+SGST) or inter-state (IGST). Only the split and who collects it differs.
Reverse / inclusive GST
Use “Remove GST” when a price already includes tax (MRP or a tax-inclusive quote) to find the base value and the GST component.
Input tax credit
Registered businesses can claim credit of the GST paid on purchases against GST collected on sales, paying only the difference to the government.
Related tools
See our GSTR-1 Preparation Tool, TDS Return Tool and Salary Calculator.
Frequently asked questions
How do I calculate GST on an amount?
Multiply the net amount by the GST rate and divide by 100. For example, 18% GST on ₹10,000 is ₹1,800, making the total ₹11,800.
How do I remove GST from a price?
Divide the gross price by (100 + rate) and multiply by 100 to get the net amount. The GST is the gross price minus this net amount.
What is the difference between CGST, SGST and IGST?
For sales within a state, GST splits equally into CGST (central) and SGST (state). For sales between states, the entire tax is IGST collected by the centre and shared with the destination state.
What are the GST slabs in India?
The main slabs are 5%, 12%, 18% and 28%, with a 3% rate on gold and a nil rate on exempt items. Most goods and services are taxed at 18%.
Is the total tax different for intra-state and inter-state?
No. At the same rate the total GST is the same; only the split differs. Intra-state is CGST plus SGST, and inter-state is a single IGST of the same total.
Does this calculator work for inclusive prices?
Yes. Choose “Remove GST” and enter the tax-inclusive (gross) price to get the base value and the GST amount.
Disclaimer: This calculator is for general information and educational purposes only and does not constitute tax advice. Confirm the applicable GST rate, HSN/SAC code and place of supply for your transaction. © ClearTax Advisors.