GST Calculator India
Himanshu Grewal
Founder • Calculator Tool Developer
Builds fast, accurate, and user-friendly online calculators for finance, education, and everyday use.
View full profile →Add or remove GST on any amount at the new 5%, 18% or 40% rates, see the CGST, SGST or IGST split, and get the total in words.
Calculate GST
GST rate
Type of sale
Quick answer
Add GST: GST = price × rate ÷ 100, so ₹1,000 + 18% GST = ₹1,180. Remove GST: price before GST = total ÷ (1 + rate ÷ 100), so ₹1,180 ÷ 1.18 = ₹1,000. Since 22 September 2025, India's main GST rates are 5% and 18%, with 40% on luxury and sin goods.
GST Calculation Formula
There are only two formulas you need — one to add GST to a price and one to take it out of a total.
Add GST (exclusive price)
GST = Price × Rate ÷ 100
Total = Price + GST
Remove GST (inclusive price)
Price = Total ÷ (1 + Rate ÷ 100)
GST = Total − Price
How to use the calculator
- 1
Choose add or remove: pick "Add GST" if your price is before tax, or "Remove GST" if the price already includes GST (like an MRP or a bill total).
- 2
Enter the amount and rate: type the amount and choose the GST rate, such as 5% or 18%.
- 3
Read the result: see the price before GST, the GST amount, the total, and the CGST and SGST (or IGST) split.
Find the GST rate from two amounts
If you know the price before and after GST: GST % = (Total − Price) ÷ Price × 100. For ₹1,000 and ₹1,050, the rate is 50 ÷ 1,000 × 100 = 5%.
Reverse GST: Remove GST from the Total
A common mistake is to take 18% off the total. That is wrong, because the 18% was added to the smaller, pre-tax price. Use these divisors instead:
| GST rate | Price before GST | GST part of total | ₹1,000 total |
|---|---|---|---|
| 3% | Total ÷ 1.03 | Total × 3 ÷ 103 | ₹970.87 + ₹29.13 GST |
| 5% | Total ÷ 1.05 | Total × 5 ÷ 105 | ₹952.38 + ₹47.62 GST |
| 12% | Total ÷ 1.12 | Total × 12 ÷ 112 | ₹892.86 + ₹107.14 GST |
| 18% | Total ÷ 1.18 | Total × 18 ÷ 118 | ₹847.46 + ₹152.54 GST |
| 28% | Total ÷ 1.28 | Total × 28 ÷ 128 | ₹781.25 + ₹218.75 GST |
| 40% | Total ÷ 1.4 | Total × 40 ÷ 140 | ₹714.29 + ₹285.71 GST |
💡 Expert tip
₹1,180 minus 18% is ₹967.60 — not ₹1,000. Always divide by 1.18 to remove 18% GST. Taking a straight percentage off the total under-states the price and the tax on your invoice.
GST Rates in India (GST 2.0)
From 22 September 2025, the GST Council replaced the old 5–12–18–28% structure with two main slabs, 5% and 18%, and a 40% rate for luxury and sin goods, as set out by the Government of India. Common examples:
| Rate | Examples |
|---|---|
| 0% (exempt) | Fresh fruit and vegetables, milk, curd, paneer, bread and roti, school exercise books and pencils, individual life and health insurance |
| 5% | Soap, shampoo, toothpaste, butter, ghee, packaged namkeen, most medicines, tractors, spectacles |
| 18% | Most services, small cars, motorcycles up to 350 cc, air conditioners, TVs, cement, most electronics |
| 40% | Sugary and aerated drinks, larger cars, motorcycles above 350 cc, yachts, betting and online gaming, and (from 1 February 2026) cigarettes, tobacco and pan masala |
| 3% and 0.25% | 3% on gold, silver and jewellery; 0.25% on rough diamonds |
GST rates are set by HSN code, and a few products still carry older rates. Always check the exact rate for your item on your invoice, the GST portal or with your accountant.
CGST, SGST and IGST
The total GST rate stays the same. Only who collects it changes:
| Sale | Tax charged | 18% on ₹1,000 |
|---|---|---|
| Within the same state | CGST + SGST (half each) | ₹90 CGST + ₹90 SGST |
| To another state | IGST (full rate) | ₹180 IGST |
| Within a Union Territory without a legislature | CGST + UTGST | ₹90 CGST + ₹90 UTGST |
GST Examples: MRP, Gold and Medicine
| Case | Working | Answer |
|---|---|---|
| MRP ₹590 at 18% | 590 ÷ 1.18 | ₹500 + ₹90 GST |
| Bill of ₹25,719 incl. 18% | 25,719 ÷ 1.18 | ₹21,795.76 + ₹3,923.24 GST |
| Jewellery ₹75,000 at 3% | 75,000 × 3 ÷ 100 | ₹2,250 GST, total ₹77,250 |
| Goods ₹5,000 at 5% | 5,000 × 5 ÷ 100 | ₹250 GST, total ₹5,250 |
GST on MRP
The MRP printed on a pack already includes all taxes, so a shop cannot charge GST on top of it. To see how much of the MRP is GST, use "Remove GST".
GST on gold
Gold, silver and jewellery attract 3% GST on the sale value, which includes making charges.
GST on medicine
After GST 2.0, most medicines are taxed at 5%, and a number of life-saving medicines are exempt. The rate is printed on the chemist's bill; check it there.
How to Calculate GST in Excel
Put the amount in A2 and the rate in B2 (for example 18%):
| You want | Formula |
|---|---|
| GST on a price | =A2*B2 |
| Price + GST | =A2*(1+B2) |
| Price before GST from a total | =A2/(1+B2) |
| GST inside a total | =A2-A2/(1+B2) |
| CGST or SGST (half) | =A2*B2/2 |
If B2 holds 18 instead of 18%, divide by 100: =A2*B2/100. Wrap results in =ROUND(…,2) to match invoice rounding.
Interest on Late GST Payment
If GST is paid after the due date, interest is charged at 18% a year on the tax paid late, for each day of delay:
Interest = Tax × 18% × Days late ÷ 365
Example: ₹50,000 of GST paid 45 days late → 50,000 × 0.18 × 45 ÷ 365 ≈ ₹1,110. A higher rate applies in some cases, such as wrongly claimed input tax credit, so confirm with your tax adviser.
Common Mistakes
Subtracting a percentage from the total
Divide by 1.18 to remove 18% GST, do not take 18% off.
Using old 12% or 28% rates
Most of those items moved to 5%, 18% or 40% in September 2025.
Charging CGST + SGST on an inter-state sale
Sales to another state carry IGST at the full rate.
Adding GST on top of MRP
MRP already includes GST.
Why I Built This Calculator
Himanshu Grewal, Founder
After GST 2.0, many online GST calculators still show only the old 12% and 28% slabs, and most do not split CGST and SGST or show the amount in words for an invoice.
I built this one for shopkeepers, freelancers and anyone checking a bill: the new rates first, the old ones kept for older invoices, the correct reverse calculation, and the total in words ready to copy. If anything looks wrong, please let me know.
How This Calculator Was Tested
- Add 18% to ₹1,000 – ₹180 GST, ₹1,180 total, ₹90 CGST + ₹90 SGST.
- Remove 18% from ₹1,180 – back to exactly ₹1,000.
- Odd amounts – ₹25,719 incl. 18% gives ₹21,795.76 + ₹3,923.24, adding back to the total.
- IGST – inter-state shows the full GST as IGST.
- Custom rate – any rate from 0% to 100% works.
- Commas and ₹ – "₹1,25,000" is read correctly.
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Frequently Asked Questions
How do I calculate GST?
GST amount = price × GST rate ÷ 100. Total = price + GST. For ₹1,000 at 18%: GST = ₹180 and total = ₹1,180.
How do I calculate GST from the total amount?
Price before GST = total ÷ (1 + rate ÷ 100). GST = total − price before GST. For ₹1,180 including 18% GST: 1,180 ÷ 1.18 = ₹1,000, so GST is ₹180.
What are the GST rates in India now?
Since 22 September 2025, most goods and services fall in two main slabs: 5% and 18%. A 40% rate applies to luxury and sin goods. Special rates of 3% (gold, silver, jewellery) and 0.25% (rough diamonds) continue, and many essentials are exempt.
Are the 12% and 28% GST slabs removed?
Yes, for almost all items. Goods that were at 12% mostly moved to 5%, and most 28% goods moved to 18% or 40%. A few items still have older rates, so check the HSN rate for your product. The calculator keeps 12% and 28% for old bills.
How is GST split into CGST and SGST?
For a sale within the same state, GST is split equally: 18% GST = 9% CGST + 9% SGST. For a sale to another state, the full 18% is charged as IGST.
How do I calculate GST on MRP?
MRP already includes GST, so use "Remove GST". For an MRP of ₹590 at 18%: 590 ÷ 1.18 = ₹500 before GST, and GST is ₹90.
What is a reverse GST calculator?
It works backwards from a GST-inclusive total to find the price before tax and the GST amount. Choose "Remove GST" in the calculator above.
How do I find the GST percentage from two amounts?
GST % = (total − price before GST) ÷ price before GST × 100. If the price is ₹1,000 and the total is ₹1,050, the GST rate is 5%.
How is interest on late GST payment calculated?
Interest is 18% a year on the tax paid late, for the number of days of delay: interest = tax × 18% × days ÷ 365. On ₹50,000 paid 45 days late, interest is about ₹1,110.
Can I use this GST calculator outside India?
Yes. Choose your currency and the calculator formats the result for it. For Australia (10%), New Zealand (15%), Singapore (9%) and Canada (5%) the standard GST rate is filled in for you; for other countries, enter your GST or VAT rate.
What is the GST on gold?
Gold, silver and jewellery attract 3% GST on the sale value, which includes making charges. On jewellery worth ₹75,000, GST is ₹2,250.
Cite this page:
Himanshu Grewal, "GST Calculator", Free AI Calculator, https://freeaicalculator.com/finance/gst-calculator/