GST Calculator

To add GST, multiply the price by the GST rate and add it: for example, ₹1,000 at 18% GST becomes ₹1,180. To remove GST from a GST-inclusive total, divide by (1 + rate): ₹1,180 at 18% has a base of ₹1,000 and ₹180 GST. GST is split equally into CGST and SGST for sales within a state (9% + 9% at an 18% rate). Enter an amount and rate below.

Updated July 2026. Figures for FY 2025-26 (AY 2026-27).

How it is calculated

Adding GST

GST amount = price × rate. Total = price + GST. At 18%, a ₹1,000 item has ₹180 GST and a ₹1,180 total.

Removing GST (reverse)

When a price already includes GST, base = total ÷ (1 + rate). GST = total − base. This backs out the tax from an inclusive amount.

CGST and SGST split

For a sale within the same state, GST splits equally into Central GST and State GST. An 18% rate is 9% CGST + 9% SGST. For inter-state sales, the same total is charged as a single IGST.

Worked example. ₹1,000 at 18% GST: add gives ₹1,180 (₹90 CGST + ₹90 SGST); remove from ₹1,180 gives a ₹1,000 base.

Frequently asked questions

What are the GST slabs in India?

The main GST rates are 5%, 12%, 18% and 28%, with 0% on many essentials. Most services and many goods fall under 18%.

How do I remove GST from a total price?

Divide the GST-inclusive total by (1 + rate). For 18% GST, divide by 1.18 to get the base price; the difference is the GST.

What is the difference between CGST, SGST and IGST?

For sales within a state, GST is split into CGST (central) and SGST (state), each half the rate. For sales between states, the full rate is charged as IGST.

Is GST calculated on the base price or the total?

GST is charged on the taxable base price. When a displayed price is inclusive of GST, the tax is a portion already inside that total.

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