How is GST calculated in India?

GST is calculated on the taxable value of goods or services. For intra-state supplies (same state), GST is split equally into CGST and SGST. For inter-state supplies, the full GST is charged as IGST. The formula is: GST Amount = Taxable Value × GST Rate / 100.

What is the difference between CGST, SGST and IGST?

CGST (Central GST) and SGST (State GST) apply to intra-state sales (seller and buyer in same state) and are split 50-50. IGST (Integrated GST) applies to inter-state sales and imports and goes to the Central Government, which later shares with states.

How do I calculate GST on inclusive price (reverse calculation)?

If the price you see already includes GST, use reverse calculation: Taxable Value = Total Amount ÷ (1 + GST Rate %). GST Amount = Total Amount − Taxable Value. Our calculator has a toggle for this.

What are the current GST rates in India 2026?

Following GST 2.0 reforms, the main slabs are 0% (essentials), 5% (merit goods), 18% (standard rate for most goods & services), and 40% (luxury & sin goods). Some items like gold have special rates (3%). Always verify the exact rate for your HSN/SAC code.

Is this GST calculator accurate for official invoices?

Yes. The calculator uses standard Indian rounding (two decimal places) and correctly applies CGST/SGST or IGST based on place of supply. For full professional invoices with HSN, E-Way Bills, GSTR-1 reports and WhatsApp sharing, use Pinbooks GST billing software.

100% Free • No Signup • Instant

Free GST Calculator IndiaCGST • SGST • IGST

Calculate exact GST in seconds. Supports current slabs (0%, 5%, 18%, 40%), reverse calculation, intra-state & inter-state transactions. Perfect for invoices, quotations & compliance.

Accurate to 2 decimals

Updated for 2026 GST slabs

Works on mobile

GST Calculator

Accurate • Instant • Free

CALCULATION MODE

SUPPLY TYPE

Auto-detected: Intra-state

YOUR STATE

CUSTOMER STATE

QUICK GST RATESApplies to all items below

or edit per line

ITEM DETAILS

DESCRIPTION

TAXABLE VALUE (EXCL. GST)

₹

GST RATE

Line Total

₹0.00

Taxable: ₹0.00

GST: ₹0.00

CALCULATION SUMMARY

Total Taxable

₹0.00

Total GST

₹0.00

GRAND TOTAL

₹0.00

Want this auto-calculated on every invoice? → Try Pinbooks

All calculations use standard Indian GST rounding (two decimal places). This is a free educational tool.

How it works

How to Use the GST Calculator

Three simple steps to get accurate GST breakup for any transaction.

Enter Taxable Value

Type the base amount (excluding GST). Or switch to reverse mode if you only know the final price including tax.

Choose GST Rate & Type

Select 0%, 5%, 18%, 40% or enter custom. Choose Intra-state (CGST + SGST) or Inter-state (IGST) based on place of supply.

View Breakdown & Export

See instant CGST, SGST, IGST and totals. Add multiple items. Copy text or download a clean PDF for your records or client.

GST Rates 2026

Current GST Slabs in India

After the GST 2.0 reforms, India follows a simplified rate structure. Use the correct slab for your HSN/SAC code.

Exempt / Essential Items

Fresh vegetables, milk, life-saving medicines, health insurance

Merit Rate

Packaged foods, edible oil, tea, coffee, medicines (non-life saving)

18%

Standard Rate (Most Common)

Electronics, furniture, services, most consumer goods

40%

Luxury & Sin Goods

Luxury cars, tobacco, aerated drinks, pan masala

Note: Gold and silver continue at special rates (~3%). Always confirm the exact rate using the HSN code on the GST portal.

CGST vs SGST vs IGST Explained

Intra-state sales (seller & buyer in same state): GST is split into CGST + SGST (50:50).
Inter-state sales (different states): Full GST is charged as IGST.
Place of supply rules decide which tax applies. For goods it is usually where the goods are delivered; for services it follows the recipient location.

Need professional invoices?

This calculator is great for quick estimates. For auto CGST/SGST/IGST on every invoice, HSN database, E-Way Bills, GSTR-1 reports and WhatsApp delivery — use Pinbooks.

Explore Pinbooks GST Invoicing

More free tools: Invoice Generator • Quotation Maker • HSN Finder • Profit Margin Calculator • Break-Even Calculator

GST Calculation Formula

Simple, transparent math used across India.

Forward Calculation

GST = Taxable Value × GST Rate %
CGST = GST ÷ 2 (for intra-state)
SGST = GST ÷ 2 (for intra-state)
IGST = GST (for inter-state)
Total = Taxable Value + GST

Reverse Calculation (Inclusive Price)

Taxable Value = Total Amount ÷ (1 + Rate%)
GST Amount = Total Amount − Taxable Value

Example: ₹11,800 inclusive @ 18% → Taxable = ₹10,000 • GST = ₹1,800

Frequently Asked Questions

GST Calculator FAQs

How do I calculate GST for an invoice with multiple items?⌄

Add each item’s taxable value separately in the calculator. The tool sums taxable amounts and correctly applies CGST/SGST or IGST on the total. This matches how most GST-compliant invoices work.

Does GST apply on the MRP or on the selling price?⌄

GST is calculated on the taxable value (transaction value), which is usually the price at which you sell (excluding GST). MRP includes GST in many cases. Always use the actual taxable amount for compliance.

Can I use this for GSTR-1 or GSTR-3B filing?⌄

This calculator gives you the correct tax breakup for each transaction. For filing, you need aggregated data. Pinbooks automatically generates GSTR-1 ready reports from all your invoices.

What if my GST rate is not listed?⌄

Use the Custom rate input. Most goods and services fall under 0%, 5%, 18% or 40%. Enter any percentage and the calculator will compute correctly.

Is this tool useful for CAs and tax professionals?⌄

Yes. It is fast and accurate for quick checks during client meetings or invoice reviews. For day-to-day client billing and full compliance automation, most professionals use Pinbooks.

Tired of manual calculations?

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