GST Calculator
Add GST to a price, or pull the GST out of a GST-inclusive amount — at the current Indian rates (0%, 5%, 18% and 40%, plus the older 12% and 28% for invoices before 22 September 2025). The split between CGST + SGST and IGST is handled for you.
Rates as of 12 October 2026. From 22 September 2025 the GST Council replaced the 12% and 28% slabs for most goods and services with a 5% merit rate and an 18% standard rate, and added a 40% rate for a select few goods and services. A few items carry special rates (the list also has 3%, and a few precious-stone items have lower rates such as 0.25% or 1.5%), and compensation cess can still apply to a small set of goods such as tobacco products. Check the notification for your item. 12% and 28% are still listed because they apply to invoices dated before 22 September 2025. Source: GST Council, 56th meeting press release (PIB), 3 September 2025. The right rate depends on the HSN or SAC code of what you sell; confirm it with your CA.
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Start free for 3 monthsFrequently asked questions
How is GST calculated in India?
GST is a percentage of the taxable value of goods or services. For a supply within the same state, the rate is split equally into CGST and SGST (for example, 18% = 9% CGST + 9% SGST). For a supply to another state, the whole rate is charged as IGST. To add GST: tax = base × rate ÷ 100. To remove GST from a GST-inclusive price: base = gross ÷ (1 + rate ÷ 100).
What is the difference between CGST, SGST and IGST?
CGST (Central GST) and SGST (State GST) apply together when the buyer and seller are in the same state — each takes half the rate. IGST (Integrated GST) applies when the supply crosses state borders, and carries the full rate in a single component. This calculator picks the right split based on whether you choose same-state or other-state supply.
What are the GST slabs in India?
As of 12 October 2026: 5% and 18% for most supplies, 40% for a select few goods and services, and 0% for nil-rated or exempt supplies. From 22 September 2025 the GST Council replaced the 12% and 28% slabs for most goods and services with a 5% merit rate and an 18% standard rate, and added a 40% rate for a select few goods and services. A few items carry special rates (the list also has 3%, and a few precious-stone items have lower rates such as 0.25% or 1.5%), and compensation cess can still apply to a small set of goods such as tobacco products. Check the notification for your item. 12% and 28% are still listed because they apply to invoices dated before 22 September 2025. Most services fall under 18%. The correct rate depends on the HSN (goods) or SAC (services) code of what you are selling, so confirm it with your CA.
How do I remove GST from a total amount?
Choose 'GST included' in this calculator and enter the gross amount. The base (taxable) value is gross ÷ (1 + rate ÷ 100), and the GST is the difference. For example, ₹11,800 at 18% gives a base of ₹10,000 and ₹1,800 GST.
Is this GST calculator free?
Yes, completely free with no login. It uses the same money-precise calculation engine that BillForge uses on real GST invoices, so the numbers match what you would put on an invoice.