GST calculator
Add GST to a price, or work backwards from a GST-inclusive amount to find the base price and tax. Pick the rate and see the CGST and SGST split, or IGST for inter-state sales.
| Amount before GST | ₹10,000 |
| CGST @ 9% | ₹900 |
| SGST @ 9% | ₹900 |
| Total GST | ₹1,800 |
| Total amount | ₹11,800 |
How to use it
Choose whether you are adding GST to an amount or removing it from an inclusive price.
Enter the amount and pick the GST rate: 0, 0.25, 3, 5, 12, 18 or 28%.
Tick inter-state if the buyer is in another state; the tax shows as IGST instead of CGST plus SGST.
Which GST rate applies
Most services, including website development, are 18%. Restaurants are 5% without input credit, packaged food is mostly 5% or 12%, electronics and furniture are usually 18%, and luxury goods, cars and tobacco are 28%. Gold is 3%, rough diamonds 0.25%. Check the HSN or SAC code for your item on the CBIC site when in doubt.
CGST, SGST and IGST
Within a state, GST is split equally: 18% becomes 9% CGST to the centre and 9% SGST to the state. For a sale to another state, the whole 18% is charged as IGST. The total is the same; only the invoice line items differ.
Removing GST from an inclusive price
If a customer paid ₹1,180 inclusive of 18% GST, the base price is 1,180 ÷ 1.18 = ₹1,000 and the tax is ₹180. Dividing by 1.18 is the trick; subtracting 18% gives the wrong answer.
Common questions
Is this GST calculator free?
Yes, with no signup. The maths runs in your browser.
How do I find the price before GST?
Use the 'Remove GST' mode: it divides the inclusive amount by (1 + rate) rather than subtracting the percentage.
What is the GST on website development?
18% under SAC 998314 (IT design and development services).
Do I charge IGST or CGST + SGST?
CGST + SGST when the buyer is in your state; IGST when they are in another state or union territory.
Need the full version?
Businesses that invoice every day usually need more than a calculator: a billing system with customers, GST reports and WhatsApp delivery. We build those.