GST Calculator
Find the GST on a price in seconds. Add GST to an amount, or take it out of an amount that already includes it, and see the CGST and SGST halves for sales within a state or the IGST for sales between states.
How to calculate GST
- 1Enter the amount and say whether it already includes GST.
- 2Choose the GST rate and whether the sale is within a state or between states.
- 3Read the amount before GST, the tax and the total.
Adding and removing GST
To add GST: GST = amount × rate ÷ 100. To remove it from an inclusive price: amount before GST = price × 100 ÷ (100 + rate). For example, ₹11,800 including 18% GST is ₹10,000 plus ₹1,800 GST.
Current rates
Since 22 September 2025, most goods and services are taxed at 5% or 18%, with 40% for luxury and sin goods and 3% for gold and jewellery. The 12% and 28% rates applied before that date and are kept for older invoices. Check the rate for your item with your accountant or the CBIC website.
CGST, SGST and IGST
Within a state, GST is split equally between the central government (CGST) and the state (SGST): 18% becomes 9% + 9%. Between states, the whole amount is IGST.
Frequently asked questions
- What is reverse GST calculation?
- Working out the GST hidden in a price that already includes it. Choose “Includes GST” to do that.
- Is this valid for filing returns?
- It does the arithmetic correctly, but rounding rules on invoices can differ by a paisa. Use your accounting software for filing.
- Is my data stored?
- No. The calculation happens in your browser.