GST Percentage
Calculator
A GST percentage calculator helps you add Goods and Services Tax to a base price, extract GST from a GST-inclusive price, or split the total GST into CGST and SGST components for intra-state transactions. Enter your price and GST slab rate — get the full tax breakdown instantly.
Calculate GSTGST Percentage Calculators
Three GST tools — add GST to a base price, remove GST from an inclusive price, and split GST into CGST + SGST.
Add GST to Base Price
Remove GST (Find Base Price)
CGST + SGST Split
GST Slab Rates
Standard GST rate slabs and what falls under each category.
5% GST Slab
Essential goods and services: packaged food items, household necessities, economy class air travel, transport services, small restaurants. Designed for mass consumption items.
12% GST Slab
Processed foods, computers, medicines, mobile phones, business class air travel, state-run lotteries. Mid-range category for semi-essential goods.
18% GST Slab
Most services, electronics, AC restaurants, financial services, IT services, construction materials, paints, varnishes. Standard rate covering most B2B services.
28% GST Slab
Luxury and demerit goods: automobiles, tobacco, cement, aerated drinks, 5-star hotels, casinos, online gaming. Highest slab for non-essential and luxury items.
0% (Zero Rated)
Fresh fruits and vegetables, milk, bread, eggs, educational services, health services, exports. Exempt from GST to protect essential consumption.
IGST (Inter-state / International)
For transactions between different states or regions, IGST applies at the full rate (e.g., 18%) instead of being split into CGST+SGST. Integrated GST applies across regional or international boundaries.
What is GST Percentage Calculator?
Why this tool exists, what it is used for, and how Goods and Services Tax works.
The GST Percentage Calculator exists to simplify Goods and Services Tax (GST) calculations for business owners, merchants, buyers, and accountants without requiring complex spreadsheet math or tax tables.
This tool is used for adding GST to net product prices, calculating tax-inclusive invoice totals, removing GST from gross totals to find pre-tax base prices, and automatically splitting tax into CGST and SGST across standard GST tax slabs (5%, 12%, 18%, 28%).
Whether you're issuing GST invoices, verifying retail receipts, or filing monthly GST tax returns, accurate tax calculation ensures compliance and clean financial records.
GST Percentage Calculator Formula
The math behind every GST calculation — adding, removing, and splitting GST.
Add GST
500 base price at 18% GST: 500 × 1.18 = 590 total. GST = 90. CGST = 45, SGST = 45 for intra-state supply.
Remove GST
590 inclusive of 18% GST: 590 ÷ 1.18 = 500 base. GST = 590 − 500 = 90. Never multiply total by 18% — that gives the wrong answer.
CGST & SGST Split
For intra-state supply, GST is split equally: each = Rate ÷ 2. At 18%: CGST = 9%, SGST = 9%. For inter-state, full IGST applies with no split.
GST Calculator FAQs
Common questions about calculating GST.
How is GST calculated on a product?
Multiply base price (excluding GST) by GST rate divided by 100, then add to base price. Formula: Total = Base × (1 + GST% ÷ 100). Example: 1,000 at 18% GST = 1,000 × 1.18 = 1,180. GST = 180.
What is the difference between CGST, SGST, and IGST?
CGST (Central GST) and SGST (State GST) are charged together for intra-state (within the same region) transactions — each at half the GST rate. IGST (Integrated GST) is charged at the full GST rate for inter-state or import transactions. A 18% GST: intra-state = CGST 9% + SGST 9%; inter-state = IGST 18%.
How do I remove GST from a price?
Divide GST-inclusive price by (1 + GST% ÷ 100). Example: 1,180 inclusive of 18% GST: 1,180 ÷ 1.18 = 1,000 base price. GST = 180. Do NOT multiply by 18% — that gives 212.40, which is wrong.
What GST rate applies to services?
Most services attract 18% GST (e.g., IT services, consulting, financial services, telecom, professional services). Some services attract 12% or 5%. Healthcare and educational services are often exempt.
How much GST is on 10,000?
It depends on the applicable GST slab: At 5%: 500 GST, total 10,500. At 12%: 1,200 GST, total 11,200. At 18%: 1,800 GST, total 11,800. At 28%: 2,800 GST, total 12,800.
What is Input Tax Credit (ITC) in GST?
Input Tax Credit (ITC) allows registered businesses to claim credit for GST paid on purchases and use it to offset GST owed on sales. This avoids cascading taxation throughout the supply chain.
Explore Our Percentage Calculators
Six specialized tools — each built for a specific use case. Pick the one that fits your question.