Online GST Calculator India

Add or remove GST for commercial invoicing, retail billing, and freelancing with CGST, SGST, and IGST breakdowns.

₹ 10,000
₹
₹ 500 ₹ 1 Lakh ₹ 2 Lakh
Selected Rate: 18% (Standard Services, IT & Electronics)
Total Invoice Amount
₹ 11,800
(₹ 11.80 Thousand)
Net Pre-Tax Value ₹ 10,000
Total GST Tax (18%) ₹ 1,800
CGST (Central: 9%) ₹ 900.00
SGST (State: 9%) ₹ 900.00
IGST (Inter-state: 18%) ₹ 1,800.00

Comprehensive Guide to GST Calculation & Tax Compliance in India

The Goods and Services Tax (GST) is India's unified destination-based indirect consumption tax enacted on July 1, 2017. Replacing a convoluted web of legacy levies—including Central Excise Duty, Service Tax, State VAT, Entry Tax, and Octroi—GST establishes a singular nationwide economic market under the motto "One Nation, One Tax."

Mathematical Formulas for GST Computation

Depending on whether you are preparing an outward B2B invoice (adding tax to a base service charge) or evaluating a retail consumer receipt (extracting the built-in tax from an MRP), two mathematical formulas govern the calculation:

1. GST Exclusive Formula (Adding GST)
GST Amount = (Base Amount × GST Rate %) / 100 Gross Total = Base Amount + GST Amount
2. GST Inclusive Formula (Removing GST / Reverse Calculation)
Net Base Price = Total Inclusive Value / (1 + (GST Rate % / 100)) GST Amount = Total Inclusive Value - Net Base Price

Official Indian GST Slabs & Common Goods

Slab Rate Key Products & Services Covered CGST Split SGST Split
3% Gold bullion, jewelry, silver, and precious gemstones 1.5% 1.5%
5% Packaged tea, spices, sugar, apparel under ₹1,000, coal, economy air tickets 2.5% 2.5%
12% Processed dairy, ghee, cellphones, computers, business air tickets 6.0% 6.0%
18% IT software, consulting services, financial services, telecom, electronics 9.0% 9.0%
28% Motor vehicles, luxury motorcycles, air conditioners, aerated drinks (+ cess) 14.0% 14.0%

Real-World Indian Invoice Example

Consider Deepak, an independent UI/UX design consultant in Hyderabad delivering a website redesign contract to a client in Mumbai for a agreed fee of ₹1,00,000. Because IT consulting falls under the 18% GST rate:

Invoice Breakdown: Inter-State B2B Invoice

  • Taxable Base Value: ₹ 1,00,000
  • Transaction Nature: Inter-State (Telangana to Maharashtra)
  • Integrated GST (IGST @ 18%): ₹ 18,000
  • Total Invoice Billing: ₹ 1,18,000
  • Note: If the client was in Hyderabad (Intra-state), Deepak would invoice CGST @ 9% (₹9,000) and SGST @ 9% (₹9,000) instead.

Input Tax Credit (ITC) Mechanics

Under Central Board of Indirect Taxes and Customs (CBIC) rules, businesses registered on the GST Portal (gst.gov.in) can offset the ₹18,000 GST paid on design work against the GST they collect on downstream sales. Maintaining accurate monthly GSTR-1 and GSTR-3B filings ensures unbroken credit chains across the supply network.

Frequently Asked Questions on GST

What are the active GST tax slabs in India?
India follows a multi-tiered Goods and Services Tax (GST) structure: 0% for essential unpackaged food grains, 3% for gold and precious metals, 5% for packaged essentials and economy transport, 12% for processed food and business class air travel, 18% for IT services, telecom and electronics, and 28% for luxury automobiles and demerit goods.
What is the difference between GST Inclusive and GST Exclusive?
GST Exclusive means the tax amount has not yet been added to the base cost; tax is added on top. GST Inclusive (MRP pricing) means the displayed price already incorporates the GST levy; to find the true pre-tax value, reverse GST computation is applied.
When does CGST + SGST apply versus IGST in India?
For intra-state transactions (where seller and buyer reside within the same state), GST is split equally into CGST (Central GST) and SGST (State GST). For inter-state transactions (seller and buyer in different states), the entire tax is levied as IGST (Integrated GST).
What is the formula to remove GST from an inclusive amount?
The reverse GST formula is: GST Amount = Total Value - [Total Value × (100 / (100 + GST Rate %))]. For example, on an ₹11,800 inclusive bill at 18%, the base value is ₹10,000 and the GST component is ₹1,800.
What is Input Tax Credit (ITC) under Indian GST?
Input Tax Credit (ITC) allows registered businesses in India to deduct the GST paid on purchases and raw materials from their final GST tax liability on sales, preventing cascading 'tax-on-tax' effects.
What is the threshold turnover for mandatory GST registration in India?
For suppliers of goods, mandatory GST registration is required if annual turnover exceeds ₹40 Lakh (₹20 Lakh for special category states). For service providers, the turnover threshold is ₹20 Lakh (₹10 Lakh in special category states).