GST Calculator
How to use this GST calculator
Enter the amount, pick the GST rate and choose whether to add GST to a price or remove it from a GST-inclusive price.
GST formulas
Add GST: price × rate ÷ 100. Remove GST: price × rate ÷ (100 + rate). Within a state, GST splits equally into CGST and SGST. Between states it is charged as IGST.
Check the rate for your item on the official GST portal, as rates change.
Worked example
Add GST: a product costs ₹10,000 before tax and the rate is 18%. GST is ₹1,800, so the final price is ₹11,800. Within a state this is split into ₹900 CGST and ₹900 SGST. For a sale to another state, the full ₹1,800 is charged as IGST.
Remove GST: a bill shows ₹11,800 including 18% GST. The price before tax is ₹11,800 ÷ 1.18 = ₹10,000 and the GST is ₹1,800.
Tips for using GST correctly
- Always check the rate that applies to your exact product or service. Different items have different rates.
- Use CGST and SGST for sales within one state, and IGST for sales between states.
- Keep a valid tax invoice. Registered businesses usually need one to claim input tax credit.
- When a price is quoted "inclusive of GST", use the Remove GST option to find the base price.
Who should use this calculator?
Shop owners, freelancers, students and buyers can all use it to check a bill, quote a price or compare an inclusive and exclusive price. It is for quick checks. For filing returns, use your accounting software or consult a professional.
Frequently asked questions
What is the difference between CGST, SGST and IGST?
CGST and SGST apply to sales within one state. IGST applies to sales between states.
Is GST charged on the base price or on the final price?
GST is charged on the base price (the price before tax). The final price is base price plus GST.
Are the rates in the list always correct?
Rates are set by the GST Council and can change. Please confirm the rate for your item on the official GST portal.