How to use the GST Calculator
- 1 Enter the amount in rupees.
- 2 Choose add GST to a price before tax, or remove GST from a price that already includes it.
- 3 Pick the GST rate.
- 4 Read the GST amount, the total and the CGST, SGST or IGST split.
Worked example
A ₹10,000 service at 18% GST, sold within the same state. GST is ₹10,000 × 18% = ₹1,800, split into ₹900 CGST and ₹900 SGST, so the invoice total is ₹11,800. Going the other way, ₹11,800 divided by 1.18 brings you back to the ₹10,000 price before tax.
Features
Current slabs
5%, 18% and 40%, the rates in force since 22 September 2025, plus 3% for gold and silver.
Add or remove
Works forward from a base price or backwards from an inclusive price.
CGST, SGST and IGST
Intra-state sales split GST equally into CGST and SGST; inter-state sales use IGST.
Copy results
Copy the figures for an invoice or quotation.
When to use it
Invoices
Work out the GST to show on a tax invoice.
Shopping
Find the price before GST on an MRP.
Quotations
Quote clients the right inclusive price.
Small businesses
Check GST on purchases for input tax credit.
Frequently asked questions
What are the GST rates now?
Since 22 September 2025 most goods and services fall in two main slabs, 5% and 18%. A special 40% rate applies to luxury and sin goods such as tobacco products, pan masala and some large cars. Gold and silver are at 3%, and many essentials are exempt.
How do I add GST to a price?
Multiply the price by the rate and add it. ₹10,000 plus 18% GST is ₹10,000 + ₹1,800 = ₹11,800.
How do I remove GST from an inclusive price?
Divide the price by 1 plus the rate. ₹11,800 ÷ 1.18 = ₹10,000, so the GST is ₹1,800.
What are CGST and SGST?
For a sale within one state, GST is shared equally between the central government (CGST) and the state (SGST). At 18%, that is 9% each.
When is IGST charged?
On sales from one state to another, and on imports. IGST is collected by the centre at the full rate.
Who needs GST registration?
Businesses with turnover above ₹40 lakh for goods or ₹20 lakh for services (lower in some special category states) must register, as must all inter-state suppliers of goods and e-commerce sellers.
Did the old 12% and 28% slabs end?
Yes. GST 2.0 moved most items from 12% to 5% and from 28% to 18%, with a few items in the new 40% slab.
Is GST included in MRP?
Yes. The maximum retail price printed on packaged goods includes all taxes, so shops cannot add GST on top of MRP.
Results are estimates based on the official rates linked above. Confirm important figures with the issuing authority or a qualified adviser before you act on them.
Reviewed by ToolsUnlocked Team · Last updated