Work out GST on any price
This page opens our tax calculator set up for Indian GST: rupees, the 18% slab chosen, and buttons for the current 5%, 18% and 40% slabs. Choose Add GST when you have the price before tax (a quote or a wholesale rate) to get the tax and the total. Choose Remove GST when a price already includes tax (an MRP or a bill total) to find the base price and the tax inside it. Along with the total, you see how the tax divides into CGST and SGST for a sale within one state, and the IGST figure for a sale to another state. For special rates such as 3% on gold, type the rate yourself.
Updated September 2026
How to calculate GST
- 1Choose Add GST (price before tax) or Remove GST (price that includes tax).
- 2Type the amount in rupees.
- 3Tap the slab, 5%, 18% or 40%, or type another rate.
- 4Read the base price, GST, total, and the CGST and SGST halves.
Adding GST vs removing GST
Businesses usually quote prices before tax, and add GST on the invoice. Shops show prices after tax: the MRP or shelf price already has GST inside it. So the question is which number you're starting from.
Starting from the base price, the total is base × (1 + rate). Starting from an inclusive price, the base is price ÷ (1 + rate). A common mistake is to take 18% off a tax-inclusive price, which removes too much. With ₹11,800 including 18% GST, the base is ₹10,000 and the GST is ₹1,800, not ₹2,124.
The slabs after the 2025 GST reform
Rates are set per item or service code and can change, so check the official rate list or your accountant before billing.
- 0%: many essentials such as fresh food, milk and some medicines and books.
- 5%: everyday goods like packaged food, soap, toothpaste and many services.
- 18%: the standard rate for most goods and services, including electronics and most professional services.
- 40%: luxury and sin goods, such as tobacco, fizzy drinks and big cars.
- Special rates: for example 3% on gold and silver. Type these into the rate box.
Writing it on an invoice
A GST invoice shows the taxable value (the base price), the rate, and the tax. Inside one state it lists CGST and SGST as two lines, each half of the rate; across states it lists IGST as one line. The calculator shows these amounts to the paisa, so you can copy them straight onto a bill. Round only the final total if your invoice rounds.
If you need a ready invoice, the Invoice Generator adds a tax percentage to your items and makes a PDF (it shows GST as one line, so write the CGST and SGST split in its notes if you need it).
Features
- Add GST or take it out of an inclusive price
- One-tap 5%, 18% and 40% slabs
- Any other rate can be typed
- CGST and SGST split, IGST amount
- Indian number format (₹10,00,000.00)
- Works offline, nothing is sent anywhere
Frequently asked questions
How do I calculate GST on a price?
Multiply the price before tax by the rate. For ₹1,000 at 18%, GST is ₹1,000 × 0.18 = ₹180, and the customer pays ₹1,180. Pick Add GST, type 1000 and tap 18% to get this instantly.
How do I find the GST included in a price?
Divide the inclusive price by 1 plus the rate. For ₹1,180 at 18%: 1,180 ÷ 1.18 = ₹1,000 base price, so the GST inside is ₹180. Note it's not simply 18% of ₹1,180 (that would give ₹212.40, which is wrong). Pick Remove GST to do this for you.
What are the GST slabs in India now?
Since 22 September 2025, most goods and services fall under 5% or 18%, with 40% for luxury and “sin” goods such as tobacco, fizzy drinks and large cars. Many essentials are 0%, and a few items have special rates, like 3% on gold. The old 12% and 28% slabs were removed. Always check the rate for your exact item or service code (HSN or SAC).
What are CGST, SGST and IGST?
For a sale inside one state, GST is shared equally: half is Central GST (CGST) and half State GST (SGST), or UTGST in a union territory. At 18%, that's 9% + 9%. For a sale from one state to another, the whole amount is Integrated GST (IGST). The total tax is the same either way.
Is the GST charged on MRP?
MRP in India already includes all taxes. To see how much of an MRP is GST, choose Remove GST, type the MRP and pick the item's rate.
Can I use this for other countries?
Yes. Type any rate and change the currency: Australia and New Zealand also call their tax GST (10% and 15%), and the main VAT Calculator lists rates for many countries.