How to use the gst calculator
- Choose Add GST or Remove GST.
- Enter the amount and pick a GST rate.
- Read the net amount, CGST, SGST, and total.
About this tool
Add GST to find the invoice total, or remove GST to find the price before tax. The result shows the CGST and SGST split for intra-state sales. Rate buttons cover the current slabs of 5%, 18% and 40%, plus the special 3% and 0.25% rates, after the GST 2.0 changes of 22 September 2025.
GST rates after GST 2.0
From 22 September 2025 the GST Council replaced the four main slabs with a simpler structure. The 12% and 28% slabs were removed, and most goods and services moved to 5% or 18%. Always confirm the rate for your specific item in the latest notification, because classification decides the slab.
| Rate | Where it applies |
|---|---|
| 0% | Exempt items and services |
| 0.25% | Rough diamonds and some precious stones |
| 3% | Gold and silver |
| 5% | Essential items and merit-rate goods and services |
| 18% | Standard rate for most goods and services |
| 40% | Sin and luxury goods |
How to add and remove GST
To add GST, multiply the price by (1 + rate). To remove GST from a price that already includes it, divide by (1 + rate). The GST amount is the difference. Three quick examples:
- Add 18% to ₹10,000: ₹10,000 × 1.18 = ₹11,800, of which ₹1,800 is GST.
- Remove 18% from ₹11,800: ₹11,800 ÷ 1.18 = ₹10,000 before tax, and ₹1,800 GST (₹900 CGST and ₹900 SGST).
- Add 40% to ₹1,00,000: ₹1,00,000 × 1.40 = ₹1,40,000.
CGST, SGST or IGST?
When the supplier and the place of supply are in the same state, GST is split equally into CGST for the Centre and SGST for the state. In a union territory without a legislature it is UTGST. For sales between states, the full amount is charged as IGST. The total tax is the same either way, only the split on the invoice changes.
Common mistakes
- Taking the GST rate as a percentage of the inclusive price. 18% of ₹11,800 is ₹2,124, which is wrong. The correct GST inside ₹11,800 is ₹1,800.
- Using one rate for a whole invoice that mixes items taxed at different rates.
- Rounding at the wrong stage. Calculate on each line or the invoice total consistently, as your accounting software does.
What this calculator does not cover
It handles a single rate on a single amount. It does not include cess, TCS or TDS under GST, reverse charge, the composition scheme, or input tax credit. For filing, rely on your accounting software or a professional.
Frequently asked questions
How do I remove GST from an inclusive price?
Divide the total by (1 + rate). For 18% GST, divide by 1.18 to get the pre-GST price.
What is the CGST and SGST split?
For sales within a state, the GST is split equally between CGST and SGST. Inter-state sales use IGST for the full amount.
Which GST rates are available?
Since 22 September 2025 the main slabs are 5%, 18%, and 40%, with special rates of 3% (gold and silver) and 0.25% (rough diamonds). The old 12% and 28% slabs were removed. Check the latest notification for your item.
How do I calculate 18% GST on ₹1,000?
GST is ₹180, so the total is ₹1,180. To go backwards from ₹1,180, divide by 1.18 to get ₹1,000.
Is the GST rate the same for goods and services?
The same slabs apply to both, but the rate for a particular item or service depends on its classification, so check the notification for yours.