GSTCalculator
GST Calculator
Add GST to a price or take it out of a GST-inclusive amount, with the CGST, SGST and IGST split.
Enter an amount to see the GST and its split.
How it is calculated
- Add GST: GST = price × rate ÷ 100, and the total is the price plus GST.
- Remove GST: price without GST = amount × 100 ÷ (100 + rate), and GST is the amount minus that price.
- Within one state the GST is shared equally between CGST and SGST; to another state it is all IGST.
- Amounts are worked in whole paise and shown in rupees.
Example. A price of ₹1,000 before GST at 18% carries ₹180 of GST, so the total is ₹1,180: ₹90 CGST and ₹90 SGST within a state, or ₹180 IGST to another state. For ₹1,180 that already includes 18%, the price without GST is ₹1,180 × 100 ÷ 118 = ₹1,000.
Rules and sources
Rules last checked on October 19, 2026
This is an illustrative calculation for general guidance, not professional advice. Rates and limits change by notification, so confirm the applicable law before you rely on a figure.
Frequently asked questions
How do I calculate GST on a price that already includes GST?
Divide the amount by 1 plus the rate (for 18%, by 1.18) to get the price without GST. The difference is the GST. Choose "This price includes GST" and the calculator does it for you.
What is the difference between CGST, SGST and IGST?
When the supplier and the place of supply are in the same state, GST is charged as CGST (to the Centre) and SGST (to the state), half each. When they are in different states, the whole amount is charged as IGST.
Which GST rate applies to my product or service?
The rate depends on how the goods or service are classified, so this calculator does not choose it. The 0%, 5%, 18% and 40% buttons are the main slabs; check the CBIC rate schedule for your item or ask us.
Does the calculator include cess, TCS or TDS?
No. It works out GST at the single rate you enter. Compensation cess, tax collected at source and tax deducted at source are separate and are not included.