GST Calculator India
Compute CGST, SGST, IGST, reverse/inclusive taxes, and trade discounts instantly. Built for Indian businesses, chartered accountants, freelancers, and consumers.
Deducts discount from taxable turnover prior to GST assessment (Sec 15 CGST Act).
Tax Invoice Breakdown
ExclusiveUnderstand GST at a Glance
Real-time proportional scale displaying the division between net goods value and tax liability.
Tax is apportioned equally 50/50 between Central Government and State jurisdiction.
Compare Entered Amount Across All GST Slabs
Instant comparison showing how your transaction would be priced under each standard Indian GST slab (0%, 5%, 12%, 18%, 28%).
| GST Slab | Applicable Goods / Services | Base Price | GST Tax Amount | Grand Total |
|---|
GST Calculation Formulas Explained (With Worked Examples)
1. GST Exclusive (To Add GST)
Used when you quote a pre-tax base amount and need to calculate the statutory tax to charge your customer on top.
GST Amount = (10,000 × 18) / 100 = ₹1,800
Total Payable = 10,000 + 1,800 = ₹11,800.
2. GST Inclusive (To Remove / Reverse GST)
Used when an item has an all-inclusive retail MRP, and you need to separate the true taxable income from the tax collected.
Base Taxable = (11,800 × 100) / 118 = ₹10,000
GST Component = 11,800 - 10,000 = ₹1,800.
Understanding CGST, SGST, and IGST Under Indian Tax Law
Central GST (CGST)
Levied under the CGST Act 2017 on transactions occurring entirely within the boundaries of a single Indian state. It accounts for exactly 50% of the total applicable GST rate.
State GST (SGST)
Levied simultaneously alongside CGST under the respective State's GST Act on intra-state supply. It accounts for the other 50% of the total GST rate collected.
Integrated GST (IGST)
Levied under the IGST Act 2017 when supply crosses state or union territory borders, or during cross-border imports into India. It is collected directly at 100% by the Central Government.
Overview of Indian GST Rate Slabs & HSN/SAC Classifications
| Slab Rate | Classification | Representative Goods & Commodities | Representative Services |
|---|---|---|---|
| 0% (Nil) | Exempt Necessities | Fresh milk, raw vegetables, unbranded grains, salt, eggs, bread | Basic postal services, judicial processes |
| 5% | Essential Items | Packaged paneer, tea, coffee, edible oil, footwear under ₹1,000, life-saving drugs | Domestic economy air travel, railway tickets |
| 12% | Standard Commodities | Computers, processed fruit, butter, cheese, diagnostic test kits, books | Non-AC hotels, business class air travel |
| 18% | Primary Standard (Most Common) | Capital goods, machinery, hair oil, toothpaste, industrial parts | IT software, telecom, banking, insurance, restaurant dining |
| 28% | Luxury & Demerit (Sin) | Motor cars, high-end motorbikes, air conditioners, cigarettes, pan masala | Five-star hotel accommodation, betting, amusement parks |
Who Benefits From Spireix GST Calculator?
Retail Merchants & Shopkeepers
Extract embedded taxes from MRP prices to maintain accurate monthly sales registers and input credit logs.
Freelancers & Agencies
Generate accurate client invoices with itemized 18% SAC service tax, discounts, and print-ready memos.
Chartered Accountants & Tax Pros
Verify client return schedules, spot-check supplier bills, and compute reverse GST in seconds without spreadsheet errors.
E-commerce Sellers
Calculate net seller payout after market commission GST and compute interstate IGST for customer shipments.
Civil Engineers & Contractors
Estimate procurement material taxes (cement, steel, machinery) and works contracts under composite tax rates.
Everyday Shoppers
Check bills and restaurant receipts to ensure tax has been applied honestly without overcharging.
Frequently Asked Questions (FAQ)
What is a GST calculator?▾
A GST calculator is an online financial utility that computes the Goods and Services Tax (GST) payable on a given base amount or extracts the net base amount and tax fraction embedded within a GST-inclusive price.
How is GST calculated in India?▾
For GST-exclusive amounts, GST Amount = (Base Amount × GST Rate) / 100, and Grand Total = Base Amount + GST Amount. For GST-inclusive pricing, Base Amount = Inclusive Amount / (1 + GST Rate / 100), and GST = Inclusive Amount - Base Amount.
How do I calculate 18% GST?▾
To calculate 18% GST on a base of ₹10,000, multiply ₹10,000 by 0.18, giving ₹1,800. The grand total is ₹11,800. For an intra-state sale, this is split into ₹900 CGST and ₹900 SGST.
What is CGST, SGST, and IGST?▾
CGST is Central GST collected by the Union government, and SGST is State GST collected by the State government for sales within the same state. IGST is Integrated GST levied on interstate sales or imports and collected solely by the Central government.
How do I remove GST from an inclusive amount?▾
Switch the calculator mode to "GST Inclusive (Remove / Reverse Tax)" or calculate: Base = Total Amount / (1 + Rate / 100). Subtracting the base from the total gives the tax amount paid.
Can I apply trade discounts before calculating GST?▾
Yes. As outlined in Section 15 of the CGST Act, trade discounts granted before or at the time of supply reduce the taxable value. You can toggle the discount switch on our calculator to apply flat or percentage reductions.
Are results from this GST calculator legally binding?▾
No. These calculations provide accurate mathematical estimates based on official formulas. Actual tax obligations depend on official HSN/SAC codes, reverse charge mechanisms, exemptions, and GST Portal filings.