How is GST calculated?
To add GST, multiply the price by the rate and divide by 100, then add that to the price. To remove GST from an inclusive price, multiply by 100 and divide by 100 plus the rate. Enter the amount and rate in FixDoks's GST Calculator to see the tax, the CGST, SGST or IGST split and final price.
GST Calculator at a glance
| Inputs | Amount, GST rate or slab, within state or other state |
|---|---|
| Output | GST amount, CGST/SGST or IGST split, final price |
| Processing | In your browser; your files are not uploaded |
| Price | Free |
| Works on | Chrome, Edge, Safari and Firefox on Windows, Mac, Android and iPhone |
How to use GST Calculator
- Choose Add GST if your price is before tax, or Remove GST if it already includes tax.
- Enter the amount and tap a GST slab, or type any rate.
- Pick Within state for CGST + SGST or Other state for IGST.
- Read the tax amount, the split and the final price. Copy the result for your invoice.
GST slabs in India after GST 2.0
From 22 September 2025, following the 56th GST Council meeting, India moved to a simpler rate structure. Most goods and services now fall into two main slabs, 5% and 18%, with a special 40% rate for luxury and sin goods. The old 12% and 28% slabs were largely removed, with most items moving down to 5% or 18%. Tobacco products moved to 40% from 1 February 2026, when the compensation cess ended.
| Rate | Typical items |
|---|---|
| 0% (nil or exempt) | Fresh milk, fresh vegetables, many unprocessed foods, individual life and health insurance |
| 5% | Many packaged foods and daily-use items, some medicines, several items moved down from 12% |
| 18% | Most goods and services, including most electronics and many items moved down from 28% |
| 40% | Luxury and sin goods such as pan masala, tobacco, aerated sugary drinks and larger cars |
| 3% and 0.25% | Gold, silver and jewellery (3%), rough diamonds (0.25%) |
The rate for a specific item depends on its HSN or SAC code, so check the CBIC rate notification or ask your accountant. The (old) buttons for 12% and 28% are there for checking invoices issued before the change.
How do I add GST?
GST amount = Price × Rate ÷ 100, and Total = Price + GST amount.
Example: a service billed at ₹1,000 with 18% GST. GST = 1,000 × 18 ÷ 100 = ₹180. The customer pays ₹1,180.
How do I remove GST from an inclusive price?
Price before GST = Inclusive price × 100 ÷ (100 + Rate), and GST = Inclusive price − Price before GST.
Example: an item sold at ₹1,180 including 18% GST. Base = 1,180 × 100 ÷ 118 = ₹1,000, and GST = ₹180. A common mistake is to take 18% of ₹1,180, which gives ₹212.40 and is wrong.
CGST, SGST and IGST
For a sale within one state (intra-state), GST is split equally into Central GST and State GST. At 18%, that is 9% CGST and 9% SGST. In a Union Territory without a legislature, UTGST replaces SGST. For a sale from one state to another (inter-state), the whole amount is charged as Integrated GST, 18% IGST. The total tax is the same either way. Only the split, and which government receives it, changes.
Who should use this
Shop owners preparing bills, freelancers invoicing clients, and buyers who want to check how much tax is inside an MRP. The tool does rounding to two decimals. On GST invoices, the tax is usually calculated per line item and then totalled, so large invoices may differ by a paisa or two.
Results are estimates for planning. Your bank, fund house or the tax department may round differently or apply extra charges, so check the final figure with them.