Business
GST Calculator
Add GST to a price, or work out the price before GST from an amount that already includes it. Shows the CGST and SGST split for sales within a state; works for VAT and other countries’ GST too.
How to calculate GST
Adding GST to a price before tax is a single multiplication. Removing GST from a price that already includes it is a division: subtracting the rate from the total gives the wrong answer.
GST = Amount × Rate ÷ 100
Amount before GST = Total ÷ (1 + Rate ÷ 100)
For an amount that already includes GST.
Example
- Price including 18% GST
- ₹1,180
- Before GST = 1,180 ÷ 1.18
- ₹1,000
- GST = 1,180 − 1,000
- ₹180
- Wrong way: 18% of 1,180
- ₹212.40
GST rates in India
Since 22 September 2025 (the “GST 2.0” rate change), most goods and services fall into two main slabs, with a higher rate for a short list of luxury and sin goods.
| Rate | Applies to (examples) |
|---|---|
| 0% | Fresh food, unbranded staples, many essentials |
| 5% | Everyday goods such as packaged food, edible oils, footwear up to ₹2,500 |
| 18% | The standard rate: most services (including IT and consulting), electronics, most other goods |
| 40% | Luxury and sin goods, such as aerated drinks and large cars |
| 28% | Tobacco and pan masala, until compensation cess ends |
| 3% and 0.25% | Gold and silver; rough precious stones |
Rates are set item by item by HSN or SAC code; confirm the rate for your product or service before you invoice.
CGST, SGST and IGST
On a sale within one state, the GST is split equally: half CGST (central) and half SGST (state, or UTGST in a union territory). 18% GST is 9% CGST plus 9% SGST. On a sale to another state, the full 18% is charged as IGST. The total tax is the same either way. To bill a client with the right breakdown, use the invoice generator.
Common mistakes
Taking 18% off an inclusive price
GST was added to the price before tax, not to the total. Divide by 1.18 instead; 18% of the total overstates the tax.
Charging CGST + SGST across states
For a buyer in another state, charge IGST. Using the wrong type means the buyer cannot claim the credit easily.
Pricing without the tax
Consumer prices are usually quoted including GST. Work back to the price before tax so your margin is right: see the profit margin calculator.
Frequently asked questions
How do I calculate GST on an amount?
How do I remove GST from a total?
What are the GST rates now?
What is the difference between CGST, SGST and IGST?
Last reviewed 4 October 2026. This tool runs in your browser; nothing you enter is stored or sent to Boostlix.