GST calculator
| Base amount | |
| GST at 18% | |
| Final amount |
How GST works on a bill
Goods and services tax is charged as a percentage of the base price. Since 22 September 2025 most goods and services sit in two slabs, 5% and 18%, with 40% for a short list of items such as tobacco products and some luxury goods. Some items are nil-rated or have special rates, so check the rate for your item or service before relying on a result.
Removing GST from a bill is not the same as subtracting the percentage. If a bill of 1,180 rupees includes 18% GST, the base price is 1,000 rupees and the tax is 180, because the tax was charged on the base, not on the final total. This calculator divides the bill by one plus the rate, which is the correct way to work backwards.
Source for the slab change: Press Information Bureau note on GST rate reforms. Businesses registered under GST should ask their accountant about input tax credit on their purchases.