GST calculator India
Add GST to any base price or extract it from a GST-inclusive amount. Supports all Indian tax slabs with CGST, SGST, and IGST splits shown instantly.
What is GST?
India's Goods and Services Tax is a destination-based consumption tax that replaced a patchwork of older central and state taxes in July 2017. It's split into CGST (Central), SGST/UTGST (State/UT), and IGST (Integrated, for inter-state transactions). For most intra-state transactions, the total GST splits evenly: 18% GST means 9% CGST + 9% SGST.
This calculator handles the two most common scenarios: adding GST to a net price (what you see on invoices to businesses) and extracting GST from a GST-inclusive total (what consumers see on MRP-inclusive receipts). Pick the standard rate slabs — 5%, 12%, 18%, 28% — or compute 0% for exempt items.
GST rate slabs
GST in India is structured in slabs:
- 0% (exempt): Essential items — fresh produce, milk, unpackaged grains, healthcare, education.
- 5%: Packaged essentials — tea, coffee, edible oils, coal, footwear under ₹1,000, economy travel.
- 12%: Processed foods, ghee, butter, mobile phones, business-class travel, state lotteries.
- 18%: Most services, soaps, toothpaste, industrial intermediates, restaurants (with AC), IT services.
- 28%: Luxury cars, tobacco, aerated drinks, premium appliances, five-star hotels — often with additional cess.
The GST formulas
Two clean formulas cover every case:
Add: GST = Amount × (Rate ÷ 100)
Extract: Base = Total ÷ (1 + Rate ÷ 100)Common Uses
- Invoice preparation: Calculate the exact GST amount to add to a service or product invoice, separating CGST, SGST, and IGST components.
- Price discovery before purchase: Determine the final GST-inclusive price of a product before buying to avoid surprise charges at checkout.
- Reverse GST calculation: Work backwards from an MRP to find the base price and GST component — useful for auditing supplier invoices.
- Input tax credit planning: Businesses calculate the GST paid on purchases to estimate ITC available for offsetting against output tax liability.
- GST return reconciliation: Accountants use the calculator to verify line-item GST figures before filing GSTR-1 and GSTR-3B returns.
- Export invoice compliance: Zero-rated exports still require correct GST documentation — calculate the applicable rate to ensure compliance.
- Freelancer billing: Service providers calculate 18% GST on professional fees for invoicing clients and tracking GST liability for quarterly returns.
FAQ
What are the GST rates in India?
GST in India has four main slabs: 5% (essentials), 12% (processed foods, computers), 18% (most services, consumer electronics), and 28% (luxury and sin goods). A few categories are exempt (0%) or taxed at special rates like 0.25% and 3%.
What's the difference between adding and extracting GST?
Add GST when you know the base price and need the total — typical for B2B invoices and price calculations. Extract GST ("reverse GST") when you have a GST-inclusive total and need to find the base price — useful for splitting consumer receipts or calculating input tax credit.
How are CGST, SGST, and IGST calculated?
For intra-state supplies, GST is split equally between CGST (central) and SGST/UTGST (state or union territory). If the rate is 18%, that's 9% CGST + 9% SGST. For inter-state supplies, a single IGST of the full rate applies instead.
How do I reverse-calculate GST from a total?
To extract GST from an inclusive price, divide by (1 + rate/100). For 18%: base = total ÷ 1.18, and GST = total − base. The calculator uses this formula automatically in "Extract" mode.
Does the GST calculator store my data?
No. All calculations run entirely in your browser. No amounts or tax figures are sent to a server or stored after you close the page.
What is the difference between GST exclusive and GST inclusive?
GST exclusive means the price does not include tax — the calculator adds GST on top. GST inclusive means the price already includes tax — the calculator extracts the GST portion from it.
By the Numbers
- India's GST system has 4 tax slabs: 5%, 12%, 18%, and 28%, with essential goods at 0%
- India collected a record ₹2.37 lakh crore in GST in April 2024 (Ministry of Finance)
- GST subsumed 17 central and state indirect taxes — including VAT, service tax, and excise duty — when launched in July 2017
- Over 1.5 crore businesses are registered under India's GST system (GSTN, 2024)