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GST Calculator
Add GST to a price, or take GST out of an amount that already includes it. See the CGST and SGST split for a buyer in your state, or IGST for a buyer in another state.
Eleven Thousand Eight Hundred Rupees Only
GST formula
GST = Price × Rate ÷ 100
Total = Price + GST
Price = Amount × 100 ÷ (100 + Rate)
GST = Amount − Price
For example, a ₹10,000 sale at 18% to a buyer in the same state has ₹900 CGST and ₹900 SGST, ₹1,800 GST in total, and a total of ₹11,800. To the same buyer in another state, it is ₹1,800 IGST.
This calculator gives the arithmetic. The right rate for an item depends on its HSN or SAC code; confirm it with your accountant or the GST portal.
Frequently asked questions
How do I add GST to a price?+
Multiply the price by the GST rate and divide by 100, then add it to the price. For ₹1,000 at 18%: GST is ₹180 and the total is ₹1,180.
How do I remove GST from an amount that already includes GST?+
Divide the amount by (100 + rate) and multiply by 100 to get the price before GST. For ₹1,180 at 18%: 1,180 × 100 ÷ 118 = ₹1,000, so the GST is ₹180.
When is GST split into CGST and SGST?+
When the seller and the buyer are in the same state, GST is split equally: 18% becomes 9% CGST and 9% SGST. When they are in different states, the full rate is charged as IGST.
What are the GST rates now?+
From 22 September 2025 most goods and services are taxed at 5% or 18%, with 40% for some luxury and sin goods and 0% for exempt items. A few items still use other rates. Check the rate for your HSN or SAC code with your accountant.
Is my calculation saved anywhere?+
No. The calculator runs in your browser. Nothing you type is sent to us or stored.