What this tool does
18% GST calculator opens the gst calculator tool with this setting ready, so you only fill in your details.
Shops, freelancers and buyers often need to know the GST inside a price. Add GST gives the final price from a price without tax. Remove GST works backwards from a price that already includes GST, the way a bill total is shown. For a sale within your state, the GST is split equally into CGST and SGST; for a sale to another state, it is all IGST. Since 22 September 2025 the main GST rates are 5%, 18% and 40%.
How to use it
- Choose Add GST or Remove GST.
- Enter the price.
- Pick the GST rate or type your own.
- Read the GST and the CGST, SGST or IGST split.
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Questions people ask
How do I calculate GST on a price?
Multiply the price by the rate. 18% GST on ₹1,000 is ₹180, so the price with GST is ₹1,180.
How do I remove GST from a total (reverse GST)?
Divide the total by 1 + rate. For ₹1,180 at 18%: 1,180 ÷ 1.18 = ₹1,000 before GST, and ₹180 is the GST.
What are the GST rates now?
Since 22 September 2025 most goods and services are at 5% or 18%, with 40% for a few luxury and sin goods. Gold is 3%.
When is it CGST + SGST and when IGST?
Within the same state the GST is split half CGST and half SGST. To another state it is charged as IGST.