GST Calculator
GST = price × rate ÷ 100, so ₹10,000 plus 18% GST is ₹11,800, split as ₹900 CGST and ₹900 SGST within a state or ₹1,800 IGST between states. To remove GST from an inclusive price, divide by (1 + rate ÷ 100): ₹11,800 ÷ 1.18 = ₹10,000.
By the Calculators With Steps team · Updated November 10, 2026 · How we check our math
- Taxable value (before GST)
- ₹10,000.00
- Total GST @ 18%
- ₹1,800.00
- CGST @ 9%
- ₹900.00goes to the Centre
- SGST / UTGST @ 9%
- ₹900.00goes to the state
- Total price (incl. GST)
- ₹11,800.00
- Taxable value₹10,000.00
- CGST₹900.00
- SGST₹900.00
Step-by-step working
- GST = amount × rate ÷ 100 = ₹10,000.00 × 18 ÷ 100 = ₹1,800.00
- Total = amount + GST = ₹10,000.00 + ₹1,800.00 = ₹11,800.00
- Within a state the GST is split equally: CGST 9% = ₹900.00 and SGST 9% = ₹900.00
Rates as of the GST rate rationalisation effective 22 September 2025 (pan masala and tobacco moved to the new rates on 1 February 2026). The right rate depends on the HSN/SAC code of the item or service, so check the rate notification for your product. Invoices may round GST to the nearest rupee.
How to use the GST calculator
- Add GST or remove GST – choose Add GST when your price is before tax (GST-exclusive), and Remove GST when the price already includes GST, such as an MRP or a restaurant bill total.
- Amount – the price in rupees.
- GST rate – pick 5%, 18% or 40%, a special rate for gold or diamonds, the old 12% or 28% rate for invoices dated before 22 September 2025, or type any other rate.
- Type of supply – within a state splits the tax into CGST and SGST; between states shows it as IGST.
The result shows the taxable value, the GST amount, its split and the final price, and the working is shown step by step so you can copy it into an invoice or an exam answer.
GST formulas
Adding GST (price before tax known):
- GST amount = original price × GST rate ÷ 100
- Price including GST = original price + GST amount
Removing GST (GST-inclusive price known):
- Price before GST = inclusive price × 100 ÷ (100 + GST rate)
- GST amount = inclusive price − price before GST
A common mistake is to take 18% of the inclusive price. On ₹11,800, 18% is ₹2,124, which is wrong. The GST inside ₹11,800 is ₹1,800, because it was charged on ₹10,000, not on ₹11,800.
Worked examples
| Example | Price before GST | GST | Price with GST |
|---|---|---|---|
| ₹10,000 at 18% (add) | ₹10,000 | ₹1,800 (₹900 CGST + ₹900 SGST) | ₹11,800 |
| ₹11,800 at 18% (remove) | ₹10,000 | ₹1,800 | ₹11,800 |
| ₹1,000 at 5% (add) | ₹1,000 | ₹50 | ₹1,050 |
| ₹1,000 at 40% (add) | ₹1,000 | ₹400 | ₹1,400 |
| ₹1,00,000 gold at 3% (add) | ₹1,00,000 | ₹3,000 | ₹1,03,000 |
For the inter-state version of the first example, the same ₹1,800 is charged as IGST at 18% instead of CGST plus SGST. The buyer pays the same total either way.
GST rates after the September 2025 reform
The 56th GST Council meeting replaced the four main slabs (5%, 12%, 18% and 28%) with a simpler structure that applies from 22 September 2025:
| Rate | What it covers (examples) |
|---|---|
| 0% (exempt) | Fresh food, UHT milk, paneer, roti and paratha, individual life and health insurance, 33 life-saving drugs |
| 5% | Most packaged food, soap, shampoo, toothpaste, most medicines, hotel rooms up to ₹7,500 a night, salons and gyms |
| 18% | Most other goods and services, including TVs, ACs, cement, small cars and motorcycles up to 350cc |
| 40% | Pan masala, cigarettes and tobacco, sugary aerated drinks, larger cars, motorcycles above 350cc, yachts |
| 3% | Gold, silver and jewellery |
| 0.25% | Rough diamonds and some precious stones |
Pan masala and tobacco products moved to 40% only on 1 February 2026, when the compensation cess on them was withdrawn. The exact rate always depends on the HSN or SAC code, so check the rate notification before you change prices in your billing software.
Which GST rate applies: CGST and SGST or IGST?
GST is a destination-based tax. If the supplier and the place of supply are in the same state, the invoice shows CGST and SGST at half the rate each (UTGST replaces SGST in Union Territories such as Chandigarh). If they are in different states, or the sale is an import, the invoice shows IGST at the full rate. Exports are zero-rated. Registered businesses can usually claim input tax credit for GST paid on purchases, which is why a business compares prices before GST while a consumer compares the final price.
Tips for businesses and shoppers
- Quote B2B prices before GST and state the rate, so the buyer can see what is claimable as input tax credit.
- Keep the old rates for old invoices. Credit notes and revised invoices for supplies made before 22 September 2025 still use the rate that applied on that date.
- Round on the invoice, not in between. Work out GST on the full taxable value and round the final figure, rather than rounding CGST and SGST separately.
- Check percentages quickly with the percentage calculator, and use the profit margin calculator to price products so your margin is calculated on the pre-GST price.
GST Calculator: frequently asked questions
How do I calculate GST on an amount?
Multiply the amount by the GST rate and divide by 100. GST at 18% on ₹10,000 is 10,000 × 18 ÷ 100 = ₹1,800, so the price including GST is ₹11,800. Within a state this is split into ₹900 CGST and ₹900 SGST.
How do I calculate GST from the total amount?
Divide the GST-inclusive price by (1 + rate ÷ 100) to get the price before GST, then subtract. For ₹11,800 including 18% GST, the base price is 11,800 ÷ 1.18 = ₹10,000 and the GST is ₹1,800. A quick formula for the GST part is total × rate ÷ (100 + rate).
What are the GST rates in India now?
From 22 September 2025 most goods and services fall in two slabs: 5% (merit rate) and 18% (standard rate). A special 40% rate applies to a short list of sin and luxury goods such as pan masala, cigarettes, sugary aerated drinks and large cars. Gold, silver and jewellery stay at 3%, rough diamonds at 0.25%, and many essentials are exempt.
Are the 12% and 28% GST slabs removed?
Yes. The GST Council folded almost all 12% items into 5% and almost all 28% items into 18% from 22 September 2025, with a few luxury items moved to 40%. Pan masala and tobacco kept their old rates until 1 February 2026, when they moved to 40% (bidis to 18%) and the compensation cess ended.
What is the difference between CGST, SGST and IGST?
On a sale within one state, the GST is split equally between the Centre (CGST) and the state (SGST, or UTGST in a Union Territory). On a sale from one state to another, the full rate is charged as IGST. At 18%, an intra-state sale has 9% CGST plus 9% SGST, while an inter-state sale has 18% IGST.
How do I calculate GST on MRP?
MRP already includes all taxes, so use the remove GST option. An item with an MRP of ₹1,180 at 18% GST has a price before tax of ₹1,000 and contains ₹180 of GST.
What is the GST on medicines?
Since 22 September 2025 most medicines are taxed at 5%, down from 12%. Thirty-three life-saving drugs were cut from 12% to nil, and three drugs used for cancer and rare diseases from 5% to nil. Check the HSN code on the invoice for a particular product.
What is the GST formula in Excel?
If the price before tax is in cell A2, GST at 18% is =A2*18% and the total is =A2*(1+18%). If A2 holds a GST-inclusive price, the GST part is =A2*18/118 and the price before tax is =A2/1.18.
How we checked this page: every figure in the examples and FAQs above is produced by this calculator and verified by automated tests against known answers, and the rules and rates come from the sources below. Last updated . Spotted a problem? Tell us.