GST Calculator
Free online GST calculator for India: add GST to a tax-exclusive price, strip GST from a tax-inclusive total (for example MRP or billed amount), and see CGST and SGST at half the headline rate each—useful for invoices, quotations, ecommerce listings, and expense claims when you know the applicable percentage.
Total Amount (Post-GST)
₹0.00
Total GST Amount
₹0.00
CGST (Central Tax)
₹0.00
SGST (State Tax)
₹0.00
Tax Breakdown
Base Amount
₹0.00 • 0.00%
CGST
₹0.00 • 0.00%
SGST
₹0.00 • 0.00%
Understanding India's GST and this calculator
Goods and Services Tax (GST) has applied across India since July 2017, replacing many earlier indirect taxes such as VAT, service tax, and excise in most supply chains. Whether you sell software, run a retail shop, or buy capital goods, the same broad idea applies: a stated percentage is applied to the taxable value of the supply (subject to exemptions, composition, reverse charge, and special notifications).
A dedicated GST calculator online helps you avoid spreadsheet mistakes when switching between GST inclusive and GST exclusive figures, when reconciling vendor bills, or when explaining a quote to a customer. It does not replace legal classification of your HSN/SAC or place of supply—it applies the rate you choose to the amount you enter.
Who will find this tool useful
- Small businesses checking invoice totals before issuing tax invoices or pro-forma quotes
- Freelancers and consultants validating client-facing prices at 18% or other standard slabs
- Shoppers and employees backing out GST from a single all-in price to see the pre-tax component
- Students and taxpayers learning the core formulas used in Indian GST arithmetic
Inclusive vs Exclusive GST
Depending on the transaction or pricing display strategy, GST is either added on top of the initial price or already baked into the final ticket price.
Adding GST (Exclusive)
The product cost does not include tax yet. GST is calculated on the raw base price and strictly added on top to find the Final Amount.
GST Amount = Cost × (GST% / 100)
Removing GST (Inclusive)
The Total Amount entered already contains the tax load within it. You are extracting the tax to find the original Base Price.
GST Amount = Cost - [Cost × (100 / (100 + GST%))]
CGST, SGST, and IGST Explained
- CGST (Central Goods and Services Tax):Applicable on intrastate (within the same state) transactions. This tax revenue goes to the Central Government.
- SGST (State Goods and Services Tax):Applicable alongside CGST on intrastate transactions. This revenue goes directly to the state where the transaction happened. The total GST is divided seamlessly 50/50 between CGST and SGST.
- IGST (Integrated Goods and Services Tax):Applicable entirely on interstate (between two different states) transactions or on imports/exports. IGST is collected collectively by the central government, which then apportions it efficiently to the destination state.
Standard India GST Slabs
Currently, goods and services are categorized into primarily four tiered standard GST slabs:
| Tax Slab | Common Applications |
|---|---|
| 5% GST | Essential packaged goods, transportation, apparel under ₹1000, frozen vegetables, coffee. |
| 12% GST | Computers, processed food, cell phones, business standard flight tickets, umbrellas. |
| 18% GST | Hair oil, soap, toothpaste, capital goods, restaurants, financial and banking services. |
| 28% GST | Automobiles, luxury vehicles, high-end electronics, ACs, aerated water, and gambling. |
Invoices, HSN/SAC, and compliance context
Real tax invoices must carry prescribed particulars—such as GSTIN, invoice number and date, taxable value, tax amounts, and HSN codes for goods or SAC for services—under the rules in force. The rate you use must match the correct tariff item or service category; when in doubt, confirm with the official GST rate schedule or a Chartered Accountant rather than assuming a slab from memory.
Input tax credit (ITC) is claimed in your returns based on eligible purchases and supplier compliance; this page only breaks one amount into base and tax so you can sanity-check arithmetic. For return filing, reconciliation, and audit support, continue to use your books or ERP.
Frequently asked questions
What is a GST calculator?
A GST calculator is a free online tool that works out Goods and Services Tax on a transaction amount. You can start from a tax-exclusive base and add GST to get the invoice total, or start from a tax-inclusive total and back out the base amount and tax. It helps businesses, accountants, and shoppers verify numbers quickly before raising or checking bills.
What is the difference between GST inclusive and GST exclusive?
GST exclusive means the price you enter is before tax; GST is calculated on top and the final payable amount is higher. GST inclusive means the figure already includes tax; the calculator splits that total into taxable value and GST. Retail MRP and many consumer prices are typically inclusive, while B2B quotes are often exclusive plus GST.
How is GST amount calculated from a base price (exclusive)?
Multiply the base amount by the GST rate and divide by 100. For example, ₹10,000 at 18% gives GST of ₹1,800 and a total of ₹11,800. Our calculator does this instantly for any rate you enter, including the common slabs 5%, 12%, 18%, and 28%.
How do you remove GST from a GST-inclusive price?
The taxable value equals inclusive amount × 100 ÷ (100 + rate), and GST equals the inclusive amount minus that taxable value. Equivalently, GST = inclusive amount − [inclusive amount × 100 ÷ (100 + rate)]. This reverses the tax that is already embedded in the price.
What are CGST, SGST, and IGST?
For a typical supply within the same state (intrastate), the total GST is usually levied as half CGST (Central GST) and half SGST (State GST). For supply across states or certain imports, Integrated GST (IGST) applies instead of CGST+SGST. This calculator splits the total GST equally into CGST and SGST, which matches common intrastate invoicing; for interstate sales you would normally show IGST as one line at the full rate.
Why does this tool show CGST and SGST as equal amounts?
For standard intrastate transactions, CGST and SGST are each half of the total GST rate (for example, 9% + 9% when the headline rate is 18%). The calculator reflects that 50/50 split. If your transaction is interstate, use the same total GST number but present it as IGST on your invoice instead of separate CGST and SGST lines.
What are the main GST rate slabs in India?
Most goods and services fall under nominal rates such as 5%, 12%, 18%, or 28%, with some items exempt or nil-rated and a few under compensation cess. The correct slab depends on the item’s HSN or SAC classification and notifications in force. Always confirm the applicable rate for your product or service on official GST law or with a qualified advisor—this calculator only applies the percentage you choose.
Does the GST calculator show Input Tax Credit (ITC)?
No. This page computes output tax on a single amount (tax-inclusive or tax-exclusive). ITC is settled in your GST returns based on eligible purchases, supplier compliance, and record-keeping. Use the tax and taxable value here for quick invoice or quote checks; rely on your accounting software or CA for ITC reconciliation and return filing.
Is GST the same in every state?
The GST rate for a given good or service is generally uniform across India, but place of supply rules decide whether CGST+SGST (intrastate) or IGST (interstate) applies. Some supplies, such as imports or OIDAR services, follow special rules. The calculator does not determine place of supply; it only applies the rate you enter to the amount.
Can I use this for composition scheme taxpayers?
Composition dealers pay tax at fixed turnover-linked rates and do not charge GST to customers in the same way as regular taxpayers. This calculator is aimed at standard percentage-based GST on a line amount. If you are in the composition scheme, follow your notified rate and compliance rules rather than treating yourself like a normal 18% B2B supplier.
What is reverse charge (RCM)—does this calculator handle it?
Under reverse charge, the recipient of the supply may be liable to pay GST instead of the supplier. The underlying math for “how much is 18% of this base” is the same, but who deposits the tax and how it is reported in GSTR differs. This tool is a generic percentage calculator; it does not automate RCM invoicing or return reporting.
Why might my result differ from my CA or accounting software?
Rounding per line versus per invoice, place of supply, mixed supplies, cess, discounts, credit notes, and exempt portions can all change the final tax. This calculator uses straightforward formulas on one lump-sum amount. Treat the output as a practical estimate for education and quick checks, not a substitute for statutory advice or audit-ready books.