How to use the GST Calculator
- Enter the amount.
- Choose a GST rate or type a custom one.
- Select “Add GST” or “Remove GST”.
- See the GST amount, CGST/SGST split and the final price.
GST formulas
Adding GST: GST = Amount × Rate ÷ 100, Total = Amount + GST
Removing GST: Net = Amount × 100 ÷ (100 + Rate), GST = Amount − Net
For intra-state supplies the GST is split equally into CGST and SGST. For inter-state supplies the full amount is charged as IGST.
Frequently asked questions
What are the common GST slabs in India?
The main slabs have been 5%, 12%, 18% and 28%, but rates are revised from time to time, so check the current rate for your goods or service.
Can I use this for VAT or sales tax?
Yes. The maths is the same — enter your VAT or sales-tax rate as a custom rate.