Main slabs since 22 Sep 2025: 5%, 18% and 40%. 3% is for gold and silver. Use 12% or 28% only for invoices dated before 22 Sep 2025.
Add GST to a price or take GST out of a GST-inclusive price, and see the CGST, SGST and IGST split instantly. The calculator uses the current GST slabs (5%, 18% and 40% since 22 September 2025, and 3% for gold and silver) and still lets you pick the old 12% and 28% rates for older invoices.
How to calculate GST
- Type the amount in rupees.
- Choose Add GST if the price does not include GST yet (for example, a quotation), or Remove GST if it already does (an MRP or a bill total).
- Pick the rate. The result shows the amount before GST, the GST, its CGST/SGST or IGST split and the total, with the formula used.
GST formulas with examples
Add GST: GST = amount × rate ÷ 100, and total = amount + GST. For ₹500 at 18%: GST = 500 × 18 ÷ 100 = ₹90, total = ₹590.
Remove GST (reverse GST): amount before GST = total ÷ (1 + rate ÷ 100). For a ₹590 bill at 18%: 590 ÷ 1.18 = ₹500, so the GST is ₹90. A common mistake is to take 18% of 590 (₹106.20); that overstates the tax because 590 already includes it.
| GST rate | To add GST, multiply by | To remove GST, divide by | GST inside a ₹1,000 bill |
|---|---|---|---|
| 3% | 1.03 | 1.03 | ₹29.13 |
| 5% | 1.05 | 1.05 | ₹47.62 |
| 18% | 1.18 | 1.18 | ₹152.54 |
| 40% | 1.40 | 1.40 | ₹285.71 |
| 12% (before 22 Sep 2025) | 1.12 | 1.12 | ₹107.14 |
| 28% (before 22 Sep 2025) | 1.28 | 1.28 | ₹218.75 |
CGST, SGST and IGST
When the seller and buyer are in the same state, GST is split equally into CGST (central) and SGST (state); 18% becomes 9% + 9%. When they are in different states, the whole amount is charged as IGST. The total tax is the same either way; only who collects it changes. The calculator shows both so you can use whichever your invoice needs.
GST slabs after GST 2.0 (from 22 September 2025)
| Rate | Typical items |
|---|---|
| 0% (exempt) | Fresh fruit and vegetables, milk, many essentials |
| 5% | Everyday items such as ghee, butter, paneer, namkeen, toothpaste, shampoo and many medicines |
| 18% | Most goods and services, including TVs, ACs, fridges, washing machines and most professional services |
| 40% | Luxury and sin goods, such as aerated and sugary drinks |
| 3% | Gold, silver and jewellery |
Frequently asked questions
How do I remove 18% GST from a price?
Divide the price by 1.18. The result is the amount before GST; the difference is the GST. For example, ₹1,180 ÷ 1.18 = ₹1,000, so the GST is ₹180.
Is 12% or 28% GST still charged?
Not on new supplies. Since 22 September 2025 the main rates are 5%, 18% and 40%. You may still need 12% or 28% to check or correct an invoice dated before that day, which is why the calculator keeps them.
Does the MRP include GST?
Yes. The MRP printed on a product in India is inclusive of all taxes, so use Remove GST to see the price before tax.
Can I share a calculation?
Yes. Add the values to the page address, for example ?amount=590&rate=18&mode=remove, or use Copy result to paste the breakdown into a message.
This calculator is for quick estimates and invoice checks. It is not tax advice; confirm rates and rules for your business with the CBIC rate notifications or a tax professional.
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