GST Calculator

Add / remove GST · CGST+SGST split
₹11,800
Total (with GST)
₹10,000
Base Price
₹1,800
GST Amount
₹900
CGST (50%)
₹900
SGST (50%)

GST slab guide

Related calculators

GST rates in India — quick reference

RateCommon items
0%Unbranded food grains, fresh produce, books, education, healthcare
0.25%Rough precious stones, semiprecious stones
3%Gold, silver, jewellery
5%Branded food, footwear up to ₹1000, medicines, economy flights
12%Processed food, computers, mobile phones, business class flights
18%Most goods & services, AC restaurants, IT services, hair oil, soaps
28%Luxury cars, bikes, tobacco, aerated drinks, 5-star hotels

How to calculate GST on an invoice

For a GST-exclusive base of ₹10,000 at 18%: GST = 10,000 × 0.18 = ₹1,800, invoice total = ₹11,800. On an intra-State sale this prints as CGST ₹900 + SGST ₹900; on an inter-State sale as IGST ₹1,800. Small businesses on the composition scheme instead apply 1% (traders/manufacturers) or 5% (restaurants) on turnover — the calculator above covers both forward and reverse directions.

GST-inclusive vs GST-exclusive price

A GST-exclusive price excludes tax (you add GST on top: base × 1.18). A GST-inclusive price already contains it (MRP tags on shop shelves are inclusive). To extract GST from an inclusive price — the reverse GST calculation — divide by (1 + rate): base = 11,800 ÷ 1.18 = ₹10,000, tax component ₹1,800. Flip the toggle above to 'Remove GST' to do this instantly for any MRP.

How this calculator works

The tool applies the standard GST arithmetic used on Indian invoices — forward (add GST) and reverse (extract GST) — and splits intra-State tax into CGST/SGST halves. Rates follow the GST Council slabs in force for 2026. All maths runs in your browser; nothing is stored. For a fuller walkthrough see GST Calculator Guide: how to calculate GST in India.

CGST vs SGST vs IGST: intra-state sales split GST equally into CGST + SGST. Inter-state sales charge IGST (full amount) instead. The total is the same.

Frequently asked questions

What is GST?

Goods and Services Tax — India's unified indirect tax on the supply of goods and services, replacing VAT, service tax, excise and many others since 1 July 2017.

How do I calculate GST on an invoice?

Multiply the taxable value by the GST rate and add it to the base: for ₹10,000 at 18%, GST is ₹1,800 and the invoice total is ₹11,800. Intra-State, show it as CGST ₹900 + SGST ₹900; inter-State, as IGST ₹1,800.

How do I add GST to a price?

Total = Base × (1 + GST%/100). For ₹10,000 at 18%: Total = 10000 × 1.18 = ₹11,800. GST amount = ₹1,800.

What is the reverse GST calculation formula?

Base price = Inclusive total ÷ (1 + GST%/100). For ₹11,800 at 18%: base = 11,800 ÷ 1.18 = ₹10,000, so the tax inside the price is ₹1,800.

What is CGST and SGST?

For sales within a state, GST splits equally into Central GST (CGST) and State GST (SGST). Both 50% of the total. For inter-state sales, IGST (Integrated GST) applies instead.

Who needs to register for GST?

Businesses with annual turnover above ₹40 lakh (goods) or ₹20 lakh (services) must register. Special category states and some services have lower thresholds. Voluntary registration is also allowed.