Free GST calculator for India
Use this GST calculator to estimate the tax amount on a price or to separate the base price and GST from a GST-inclusive total. Enter the amount, choose a rate and select whether your amount is before GST or already includes GST. Results are shown in Indian rupees (₹).
How to calculate GST
- Enter the amount in rupees.
- Choose the applicable GST rate from the list.
- Select Before GST if the entered amount is the base price, or Includes GST if tax is already included.
- Click Run tool to see the base amount, GST amount and total.
GST calculation examples
Adding GST: If the base price is ₹1,000 and the selected rate is 18%, GST is ₹180 and the total is ₹1,180.
Removing GST: If ₹1,180 already includes 18% GST, the base price is ₹1,000 and the GST component is ₹180.
GST formula
- GST amount on a base price: Base price × GST rate ÷ 100.
- Total including GST: Base price + GST amount.
- Base price from an inclusive total: Inclusive total ÷ (1 + GST rate ÷ 100).
The calculator performs the arithmetic for the rate you select. It does not determine the legally applicable rate, product classification, place of supply, exemptions or invoicing treatment. Confirm the correct rate for your transaction with official guidance or a qualified tax professional.
Frequently asked questions
Which GST rates can I select?
This tool provides 0%, 5%, 12%, 18% and 28% options for calculation. The rate applicable to a particular supply may depend on its classification and current rules.
Does the calculator split CGST and SGST?
No. It shows the combined GST amount. For an eligible intra-state supply, CGST and SGST are generally split according to the applicable rules; inter-state supplies may involve IGST.
Can I calculate GST from an inclusive price?
Yes. Select Includes GST to extract the base price and GST component from the total you entered.
Is this an official government calculator?
No. Tolvix is an independent utility and does not provide tax advice. Verify tax treatment before filing or issuing an invoice.
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