GST Calculator
Add GST to a price, or take it out of an amount that already includes it. You get the tax, the total and the CGST / SGST or IGST split, in rupees.
For older 12% or 28% invoices, or a cess-inclusive rate.
Total including GST
₹11,800.00
- Price before GST
- ₹10,000.00
- CGST (9%)
- ₹900.00
- SGST (9%)
- ₹900.00
- Total GST
- ₹1,800.00
- Total including GST
- ₹11,800.00
How GST is calculated
Adding GST to a price before tax:
GST = price × rate ÷ 100 · total = price + GST
₹10,000 at 18% → GST ₹1,800, total ₹11,800.
Removing GST from an amount that already includes it:
price = amount × 100 ÷ (100 + rate) · GST = amount − price
₹11,800 including 18% → price ₹10,000, GST ₹1,800. A common mistake is to take 18% of ₹11,800 (₹2,124), which overstates the tax.
CGST, SGST and IGST. A sale within one state splits the GST equally between the centre (CGST) and the state (SGST): 18% becomes 9% + 9%. A sale to another state carries the full rate as IGST.
Current rates. Since 22 September 2025, GST has two main rates, 5% and 18%, plus 40% for luxury and sin goods, 3% for gold, silver and jewellery and 0.25% for rough diamonds. The 12% and 28% slabs no longer apply to new sales.
How do I calculate GST on a price?
Multiply the price by the GST rate and divide by 100. For ₹10,000 at 18%, GST is 10,000 × 18 / 100 = ₹1,800, so the customer pays ₹11,800.
How do I remove GST from a GST-inclusive amount?
Divide the amount by (100 + rate) and multiply by 100 to get the price before tax. For ₹11,800 including 18% GST, the base price is 11,800 × 100 / 118 = ₹10,000 and the GST is ₹1,800.
What are the GST rates in India now?
Since 22 September 2025 (GST 2.0), most goods and services are taxed at 5% or 18%, with a 40% rate for luxury and sin goods. Essentials are exempt (0%), gold, silver and jewellery are taxed at 3%, and rough diamonds at 0.25%. The old 12% and 28% slabs were removed; use the custom rate if you need to check an older invoice.
When do I charge CGST and SGST, and when IGST?
On a sale within the same state, GST is split equally into CGST (central) and SGST (state); at 18%, that is 9% + 9%. On a sale to another state, or on imports, the whole 18% is charged as IGST. In union territories without their own legislature, UTGST takes the place of SGST.
Is this GST calculator free?
Yes. It runs entirely in your browser, needs no sign-up and doesn’t store the numbers you enter.
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