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GST calculator
Example: ₹1,000 before GST at 18% comes to ₹1,180, with ₹90 CGST and ₹90 SGST. Type your amount, pick the rate printed on your bill, and say whether the amount already includes GST.
This works on the rate you choose; it does not say which rate applies to a product or service. Rates are set by the GST Council and can change, so check the rate on your bill or ask the seller. This is a calculator, not tax advice, and the site is not connected with the GST Council, CBIC or GSTN.
GST rates now
Since 22 September 2025 most goods and services are taxed at 5% or 18%, a short list of luxury and sin goods at 40%, and some essentials at 0%. Gold, silver and jewellery stay at 3%. The rate for each item is set by notification, and the bill shows the rate the seller used.
Adding and taking out GST
- GST on a price before tax = price × rate ÷ 100. At 18%, ₹1,000 has ₹180 GST, so the total is ₹1,180.
- Price before tax, from a price that includes GST = price × 100 ÷ (100 + rate). ₹1,180 × 100 ÷ 118 = ₹1,000, so the GST inside it is ₹180.
CGST, SGST and IGST
When the seller is in your state, GST is split in two equal halves: CGST goes to the Centre and SGST to the state, so 18% shows on the bill as 9% CGST and 9% SGST. When the seller is in another state, as with many online orders, the whole 18% is IGST. You pay the same total either way.
Checking a bill
Packed goods carry an MRP that already includes GST, so a shop may not add GST on top of the MRP. A shop that charges GST must print its 15-character GSTIN on the bill; you can look it up on the GST portal's Search Taxpayer page. A shop under the composition scheme may not charge you GST at all, and its bill should say so.
Questions people ask
How do I calculate 18% GST?
Multiply the price before tax by 18 and divide by 100. On ₹2,500 that is ₹450, so the total is ₹2,950. Within a state the bill shows it as ₹225 CGST and ₹225 SGST.
How do I find the GST inside an MRP?
Divide the MRP by 1 plus the rate as a decimal, and take that from the MRP. For an MRP of ₹999 at 18%, 999 ÷ 1.18 = ₹846.61 before tax, so ₹152.39 is GST.
Do I pay more with IGST than with CGST and SGST?
No. IGST is the whole rate in one line, and CGST plus SGST is the same rate split in two. The total GST is the same.
What is the GST on gold jewellery?
Gold, silver and jewellery bought from a shop carry 3% GST on the whole bill, making charges included. The jewellery calculator on this site adds it for you.