What is GST?
GST (Goods and Services Tax) is India's unified indirect tax, introduced in July 2017. It replaced a web of taxes like VAT, service tax, and excise duty with a single tax on the supply of goods and services.
GST is charged at four main slabs — 5%, 12%, 18%, and 28% — depending on the product or service. Essential items are taxed lower or are exempt, while luxury goods attract the highest rate.
CGST, SGST and IGST Explained
When a sale happens within the same state, the GST is split equally into CGST (Central GST) and SGST (State GST). For example, 18% GST on an intra-state sale means 9% CGST plus 9% SGST.
When goods move between states, the full tax is collected as IGST (Integrated GST) by the central government, which then distributes the state's share. The total rate stays the same — only the split changes.
How to Calculate GST
To add GST to a price, multiply the base price by the rate: ₹1,000 at 18% becomes ₹1,000 × 1.18 = ₹1,180, with ₹180 as GST. To remove GST from an inclusive price, divide by (1 + rate): ₹1,180 ÷ 1.18 = ₹1,000.
For reverse calculation, the GST component of an inclusive price is price × rate ÷ (100 + rate). On ₹1,180 at 18%, that is 1,180 × 18 ÷ 118 = ₹180.
Why Use a GST Calculator
Manual GST math is easy to get wrong, especially for reverse calculations, multiple slabs, or when you need to file returns. A small error in tax can mean penalties or a rejected invoice.
Our GST calculator handles both add-GST and remove-GST directions instantly, for any slab. Enter the amount, pick the rate, and you get the tax and the total in one click.