This free online GST calculator helps you calculate GST (Goods and Services Tax) instantly for any product or service in India. Use it as a GST inclusive calculator, GST exclusive calculator, or reverse GST calculator — updated for the latest GST 2.0 rates (5%, 18%, 40%) effective from September 2025. Whether you're a business owner, freelancer, shopkeeper, or student, this GST percentage calculator gives accurate results in seconds, with a full CGST, SGST, and IGST breakdown.
What Is GST?
GST (Goods and Services Tax) is a single, unified indirect tax levied on the supply of goods and services across India. Introduced on 1st July 2017, GST replaced multiple older taxes such as VAT, service tax, excise duty, and octroi. It is a destination-based tax, meaning the tax is collected in the state where the goods or services are finally consumed, not where they are produced.
GST 2.0 — New GST Rates in India (2025 Reform)
On 22nd September 2025, the GST Council rolled out GST 2.0, one of the biggest tax reforms since GST launched in 2017. The old 4-tier structure (5%, 12%, 18%, 28%) was simplified into just three main slabs plus a nil rate:
| GST Slab | Applicable On |
|---|---|
| 0% (Nil Rate) | Essential food items, life-saving medicines, health and life insurance |
| 5% | Daily essentials, packaged food, agricultural goods, most medicines |
| 18% | Standard goods and services — electronics, appliances, small cars |
| 40% | Luxury and "sin" goods — tobacco, pan masala, luxury vehicles, aerated drinks |
The old 12% and 28% GST slabs have been almost entirely phased out. Most items that were earlier taxed at 12% have now moved to either 5% or 18%, while most items from the 28% slab have shifted to 18% or the new 40% luxury slab. Many online GST calculators and tax tools are still showing outdated 2017-era rates — always double-check that the calculator you use reflects the current GST 2.0 structure.
GST Calculation Formula
Remove GST (Reverse Calculation): Base Price = Total Amount ÷ (1 + GST Rate/100)
In "Add GST" mode, you enter the base (pre-tax) price and the calculator adds GST on top to give you the final invoice amount. In "Remove GST" mode, you enter the GST-inclusive total (such as an MRP or a final invoice value) and the calculator back-calculates the original base price — this is especially useful when the price you have already includes tax.
CGST, SGST, and IGST Explained
When a transaction happens within the same state (intra-state supply), GST is split equally into two components — CGST (Central GST) and SGST (State GST). For example, an 18% GST rate becomes 9% CGST + 9% SGST. When a transaction happens between two different states (inter-state supply), the full GST amount is charged as IGST (Integrated GST) instead of being split.
Reverse GST Calculator (Remove GST From Total)
A reverse GST calculator (also called a GST extraction calculator) is used when your amount already includes tax — for example, an MRP, a retail price, or a GST-inclusive invoice total — and you need to work out the base price and the GST component separately. The "Remove GST" mode on this calculator does exactly this.
⚠️ The Most Common Mistake in Reverse GST Calculation
Many people calculate "Remove GST" incorrectly by directly computing Total × Rate ÷ 100 — this is wrong and overstates the GST amount. The correct method is to first extract the base price using Base = Total ÷ (1 + Rate/100), and then calculate GST as Total − Base. This calculator automatically applies the correct formula, removing the risk of manual calculation errors.
GST Calculator for Manufacturers, Wholesalers, and Small Businesses
For manufacturers and wholesalers, GST calculation typically involves an additional step — factoring in the cost of production, profit margin, and applicable GST rate together. The standard approach is to first add your profit margin to the cost of goods to arrive at the selling price, and then calculate GST on that final selling price. This calculator's "Add GST" mode can be used directly for this — simply enter your final selling price (after profit margin) as the base amount.
Why Use This Free GST Calculator?
- Completely free online GST calculator — no login, no sign-up, unlimited use
- Updated for the latest GST 2.0 rates (0%, 5%, 18%, 40%) — many older calculators still show outdated 2017 slabs
- Works as both a GST inclusive calculator and a GST exclusive (reverse) calculator
- Instant CGST, SGST, and IGST split for both intra-state and inter-state transactions
- No data is uploaded or stored — all calculations happen instantly in your browser
How To Use This GST Calculator?
- Select "Add GST" or "Remove GST" mode depending on whether your amount excludes or includes tax
- Type in the amount
- Select the applicable GST slab (0%, 5%, 18%, or 40%)
- Choose intra-state or inter-state — the result updates instantly
Frequently Asked Questions (FAQs)
What are the new GST slabs under GST 2.0?
GST 2.0 came into effect on 22nd September 2025, simplifying the old 5%, 12%, 18%, 28% structure into just 0%, 5%, 18%, and 40% slabs.
What is the difference between GST inclusive and GST exclusive price?
A GST-inclusive price already has tax built into the total (like an MRP). A GST-exclusive price is the base value, on which GST is added separately.
What are CGST and SGST?
For transactions within the same state, GST is split equally into CGST (Central GST) and SGST (State GST). For transactions between different states, the entire amount is charged as IGST instead.
Is this GST calculator free to use?
Yes, it is completely free, with no sign-up required, and you can use it as many times as you like.
What is the most common mistake when calculating Remove GST?
People often calculate it directly as Total × Rate ÷ 100, which is incorrect. The correct formula is Base = Total ÷ (1 + Rate/100), followed by GST = Total − Base. This calculator applies the correct formula automatically.
How do I find the GST rate using an HSN code?
An HSN (Harmonized System of Nomenclature) code identifies your product's category, which determines the applicable GST rate. You can check your product's HSN code on your invoice or the official GST portal (cbic-gst.gov.in) — once you know the rate, you can select it directly (0/5/18/40%) in this calculator.
Does this calculator work for both goods and services?
Yes — the same GST calculation formula and slabs apply to both goods (identified by HSN codes) and services (identified by SAC codes).