Free tool
GST calculator
Add GST to an amount, or find the taxable value inside a GST-inclusive price. Shows the CGST and SGST split for sales within Kerala, or IGST for sales to other states.
How the calculation works
- Adding GST
- GST = amount × rate ÷ 100
Total = amount + GST - Removing GST
- Taxable value = price ÷ (1 + rate ÷ 100)
GST = price − taxable value
The calculator does not include cess. Check the rate that applies to your goods or services before invoicing.
Questions about GST calculation
Multiply the amount by the GST rate and divide by 100 to get the tax, then add it to the amount. For ₹10,000 at 18%, the GST is ₹1,800 and the total is ₹11,800.
Divide the price by 1 plus the rate as a decimal. For ₹11,800 including 18% GST, the taxable value is 11,800 ÷ 1.18 = ₹10,000 and the GST is ₹1,800.
For a sale within Kerala, the GST is split equally between the centre (CGST) and the state (SGST). For a sale to a customer in another state, the whole amount is charged as IGST. The total tax is the same either way.
The rate depends on the HSN code of the goods or the SAC code of the service. Rates are revised from time to time, so check the current rate schedule or ask us before you invoice.