GST Calculator
Add or remove GST in one tap, with an automatic CGST / SGST / IGST split. Works for the 5%, 12%, 18% and 28% slabs, built for Indian freelancers & small businesses.
How to calculate GST
GST is calculated as a percentage of the taxable value. To add GST, multiply the amount by the rate and add it on top. To remove GST from a price that already includes it, divide the total by (1 + rate). For example, on ₹10,000 at 18%:
- Add GST: ₹10,000 + 18% = ₹11,800 (₹1,800 GST)
- Remove GST from ₹11,800: base ₹10,000, GST ₹1,800
- Same state: ₹900 CGST + ₹900 SGST · Other state: ₹1,800 IGST
GST rates in India
Most goods and services fall into one of four slabs. Services are usually taxed at 18%.
- 5%: essentials, small restaurants, transport
- 12%: processed food, business-class travel, some electronics
- 18%: most services, software, professional fees
- 28%: luxury goods, cars, tobacco
Frequently asked questions
How do I calculate GST on an amount?+−
To add GST, multiply the amount by the GST rate and add it to the amount. For example, ₹10,000 at 18% GST = ₹1,800 GST, total ₹11,800. The calculator above does this instantly and splits it into CGST and SGST, or IGST for a different state.
What is a reverse GST calculation?+−
Reverse GST (or 'remove GST') works out the original pre-tax price from a GST-inclusive amount. Switch the calculator to 'Remove GST' and it extracts the base amount and the GST included.
What is the difference between CGST, SGST and IGST?+−
For a sale within the same state, GST is split equally into CGST (central) and SGST (state). For a sale to a different state, the full rate is charged as IGST (integrated). The calculator switches automatically based on the transaction type you pick.
What are the GST rates in India?+−
The main GST slabs are 5%, 12%, 18% and 28%, with 3% applying to items like gold. Most services fall under 18%.
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