0.25% GST calculator

How GST is calculated

Adding GST (exclusive amount): GST = taxable value × rate ÷ 100, and the invoice total is taxable value + GST. On ₹1,000 at 18%, GST is ₹180 and the total is ₹1,180.

Removing GST (inclusive amount): taxable value = inclusive amount × 100 ÷ (100 + rate), and GST is the difference. On ₹1,180 at 18%, the taxable value is ₹1,000 and GST is ₹180.

Amounts are rounded to the paisa. When the GST has an odd paisa, CGST takes the extra paisa so CGST + SGST always equals the total GST exactly.

CGST, SGST, and IGST

If the supplier and the place of supply are in the same state, the tax is split equally into Central GST (CGST) and State GST (SGST, or UTGST in a union territory). At 18%, that is 9% CGST and 9% SGST.

If the place of supply is in another state, the whole tax is charged as Integrated GST (IGST). At 18%, that is 18% IGST.

GST slabs after September 2025

From 22 September 2025, most goods and services fall into two main slabs: 5% and 18%. A 40% rate applies to a short list of luxury and sin goods. Most items that were at 12% moved to 5%, and most items at 28% moved to 18%.

Special rates continue for a few categories, such as 3% on gold and jewellery and 0.25% on rough diamonds. Some goods and services are exempt or nil-rated. Always confirm the rate for your HSN or SAC code in the CBIC rate notifications before you bill.