Amount (₹ / $ / any currency)
GST Rate (%)
🇮🇳 India GST 2.0 — since 22 September 2025, India's GST Council simplified the tax structure to 5%, 18%, and 40% (the 12% and 28% slabs were abolished). This calculator defaults to the current structure. If you're calculating GST on a transaction that took place before 22 September 2025, use the legacy rates below instead.
Quick slabs — current (since 22 Sep 2025)
Legacy slabs — before 22 Sep 2025 only
Mode
Full breakdown (click to copy)
Decision Support
Confirm you're using the current rate
If you're pricing a product or service today, use the current 5%/18%/40% slabs. Only use the legacy 12%/28% rates when calculating GST on a transaction dated before 22 September 2025.
CGST/SGST split assumes an intra-state sale
For inter-state transactions, the full GST amount is charged as IGST rather than split into CGST and SGST — this calculator's 50/50 split assumes a same-state sale.
GST rates are set by product/service category, not a flat rule
Don't assume every item falls under the 18% standard rate — check the correct HSN/SAC classification for your specific product before invoicing.
➜ Next step: Applying GST after a discount? Use the Discount Calculator first, then feed the discounted price into this tool. Outside India? See the VAT Calculator for other countries' rates.
How to Use the GST Calculator
- Enter the amount — either the pre-GST price (to calculate GST and final price) or the GST-inclusive price (to extract the original price).
- Select GST rate — choose from India's current rates (5%, 18%, 40%, effective since 22 September 2025), or use the legacy 12%/28% rates for transactions before that date. Or enter a custom percentage for other countries' VAT/GST rates.
- Choose calculation direction — Add GST (to find final price including GST) or Remove GST (to find the base price before GST was added).
- Read the breakdown — see original amount, GST amount (split into CGST and SGST for India), and final total.
- Use for invoicing — copy the calculated values directly into your invoice or tax return.
🇮🇳 India GST structure: GST is split equally between Central GST (CGST) and State GST (SGST) for intra-state transactions. For inter-state transactions, it becomes IGST (Integrated GST) at the full rate. Always specify which applies on your invoice.
Understanding GST
📋 What Is GST?
Goods and Services Tax — a unified indirect tax levied on the supply of goods and services. Replaced multiple cascading taxes (VAT, service tax, excise duty) in India from July 2017. Similar systems operate in Australia, Canada, Singapore, and 160+ countries.
📊 India GST Slabs (current, since 22 Sep 2025)
0%: Essential goods (many food grains, fresh produce, life/health insurance). 5%: Merit rate — everyday essentials, packaged food, agricultural inputs. 18%: Standard rate — most goods and services, electronics, restaurants. 40%: Luxury and "sin" goods — high-end cars, tobacco, aerated drinks, casinos. The previous 12% and 28% slabs were abolished in the September 2025 GST 2.0 reform.
🔢 Input Tax Credit
Businesses registered for GST can claim credit for GST paid on purchases (input tax) against GST collected on sales (output tax). Only the net amount is paid to the government — preventing tax-on-tax cascading.
🌍 International Equivalents
Australia: 10% GST. UK: 20% VAT. EU: varies 17–27%. Singapore: 9% GST. UAE: 5% VAT. Canada: 5% federal GST + provincial sales tax. The concept is identical — a consumption tax collected at each stage of the supply chain.
📅 GST Filing
In India, GST returns are filed monthly (GSTR-1 for outward supplies, GSTR-3B for summary return) or quarterly for small businesses. Late filing attracts penalties and interest. Accurate GST calculation at the time of invoicing prevents errors in returns.
⚡ Reverse Charge Mechanism
In certain specified cases, the recipient of goods/services pays GST directly to the government instead of the supplier. This applies to specific categories like import of services, purchases from unregistered dealers, and certain notified goods.
GST for Businesses and Freelancers
GST registration threshold
In India, GST registration is mandatory if annual turnover exceeds ₹40 lakhs (₹20 lakhs for service providers in special category states). Voluntarily registering below this threshold allows you to claim input tax credit, which can be beneficial if you have significant business purchases.
GST on exports
Exports of goods and services are zero-rated under GST — you charge 0% GST on export invoices and can claim refund of all GST paid on inputs used in production. This makes Indian exports more competitive globally by removing the tax cost from export pricing.
Common GST mistakes
The most frequent GST errors: using wrong GST rate for the goods/services category, failing to issue GST-compliant invoices with all required fields, not reconciling GSTR-2A with purchase records, and missing input tax credit claims. Each error can result in penalties or lost credits.
🧾 Invoice requirements: A valid GST invoice must include: GSTIN of supplier, invoice number and date, recipient details with GSTIN (for B2B), HSN/SAC code, taxable value, applicable GST rate, CGST/SGST/IGST amounts separately, and place of supply. Missing any field invalidates the invoice for input tax credit purposes.
GST Formula
GST Amount = Original Amount × GST Rate ÷ 100. To go the other way — Original Amount (removing GST from an inclusive price) = Total ÷ (1 + GST Rate ÷ 100).
Worked example
₹10,000 base price, 18% GST (current standard rate): GST Amount = 10,000 × 18 ÷ 100 = ₹1,800. Total invoice value = ₹11,800, split as CGST ₹900 + SGST ₹900 for an intra-state sale.
Assumption: uses the current India GST 2.0 structure (5%/18%/40%) by default — use the legacy rate buttons for pre-22-September-2025 transactions, and confirm your product's exact HSN/SAC classification, since rate assignment isn't always intuitive.
Common Mistakes
Using a pre-reform rate for a current transaction
Applying 12% or 28% to a sale happening today will overstate or understate the correct tax — those slabs were abolished on 22 September 2025.
Confusing "add" and "remove" mode
If your amount already includes GST, use "Remove GST" — running an inclusive price through "Add GST" double-counts the tax.
Assuming CGST/SGST always applies
The 50/50 CGST/SGST split only applies to intra-state sales — inter-state transactions use IGST at the full rate instead.
Using the wrong rate for the product category
GST rate depends on HSN/SAC classification, not a general guess — verify the correct rate for your specific goods or service before invoicing.
Frequently Asked Questions
What is GST?
GST (Goods and Services Tax) is a unified indirect tax levied on the supply of goods and services in India, replacing multiple cascading taxes. Since the GST 2.0 reform on 22 September 2025, it has three main slabs — 5%, 18%, and 40% — plus 0% for essential goods. The previous four-slab system (5%, 12%, 18%, 28%) is still relevant for transactions dated before that reform.
What is the difference between GST exclusive and inclusive?
GST exclusive means GST is added on top of the base price. If an item costs ₹1,000 with 18% GST, the final price is ₹1,180. GST inclusive means the price already includes GST — so ₹1,180 inclusive = ₹1,000 base + ₹180 GST.
What is CGST and SGST?
For intra-state (within the same state) transactions, GST is split equally into CGST (Central GST) and SGST (State GST). For a total 18% GST rate, CGST = 9% and SGST = 9%. For inter-state transactions, IGST (Integrated GST) applies at the full rate.
Which items fall under the 40% GST slab?
Since the September 2025 GST 2.0 reform, luxury and "sin" goods attract 40% GST — high-end cars, motorcycles above 350cc, cigarettes, aerated drinks, casinos, and premium consumer durables. Before the reform, this category was taxed at 28% (sometimes with an additional cess). If you're calculating GST on a transaction from before 22 September 2025, use the legacy 28% rate instead.
How do I calculate GST on a price?
To add GST: Final Price = Original Price × (1 + GST%/100). To remove GST from an inclusive price: Original Price = Inclusive Price ÷ (1 + GST%/100). This calculator handles both automatically.
References
🏛️ Goods and Services Tax Council (India)
Official GST rates and the September 2025 GST 2.0 reform — gstcouncil.gov.in
🏛️ GST Portal
Official GST registration, filing, and rate lookup — gst.gov.in
Last updated: 15 July 2026 · Reflects India's GST 2.0 structure (5%/18%/40%), effective 22 September 2025. Legacy 12%/28% rates are provided for pre-reform transactions only — always verify the exact rate for your product/service category via the GST Portal.