How do you calculate GST (Add GST formula)?

To add GST to a net amount: GST Amount = (Net Price × GST Rate) ÷ 100. Total Price = Net Price + GST Amount.

How do you remove GST from a total price (Reverse GST formula)?

To remove GST from an inclusive amount: Base Net Price = Gross Total ÷ (1 + (GST Rate ÷ 100)). GST Amount = Gross Total - Base Net Price.

What are CGST, SGST, and IGST?

In dual-GST tax systems like India, CGST (Central GST) and SGST (State GST) are split equally (50/50) on sales within the same state (intra-state). IGST (Integrated GST) applies at the full tax rate on sales between different states (inter-state).

Is the GST Calculator tool completely free?

Yes, our GST Calculator is 100% free with no account creation, no subscriptions, and unlimited usage across all devices.

How is GST calculated on a net price (Add GST)?

GST Amount = (Net Amount * GST Rate) / 100. Total Gross Price = Net Amount + GST Amount.

How do you calculate Reverse GST (Remove GST from gross total)?

Net Base Amount = Gross Total / (1 + (GST Rate / 100)). GST Amount = Gross Total - Base Net Amount.

What is the difference between CGST, SGST, and IGST?

For intra-state transactions (within the same state), GST is split equally between CGST (Central GST) and SGST (State GST). For inter-state transactions (between two different states), full IGST (Integrated GST) applies.

What are the common GST tax slabs in India?

The primary GST tax rates in India are 0% (essential food items), 5% (household essentials, transport), 12% (processed foods, computers), 18% (services, consumer goods), and 28% (luxury items, automobiles).

Is this GST calculator safe and free to use?

Yes, it is 100% free with no login or sign-up needed. All calculations run strictly in your web browser, ensuring complete privacy for your financial figures.

How is GST calculated on a net amount?

GST Amount = (Net Amount × GST Rate) ÷ 100. The Total Gross Price = Net Amount + GST Amount.

How do I remove GST from an inclusive price (Reverse GST)?

Net Base Amount = Gross Amount ÷ (1 + (GST Rate ÷ 100)). The GST Amount = Gross Amount - Net Base Amount.

What is the difference between CGST, SGST, and IGST?

For intra-state transactions (within the same state), GST is split equally between CGST (Central GST) and SGST (State GST). For inter-state transactions (between different states), full IGST (Integrated GST) is charged.

Is this GST calculator free and private?

Yes, 100% free with no login required. All calculations run entirely inside your browser, ensuring complete privacy for your business and financial figures.

Is GST Calculator free on OnlineToolsZone?

Yes. GST Calculator is free to use here with no signup required for typical workflows.

How do you calculate GST (Add GST formula)?

To add GST to a net amount: GST Amount = (Net Price × GST Rate) ÷ 100. Total Price = Net Price + GST Amount.

How do you remove GST from a total price (Reverse GST formula)?

To remove GST from an inclusive amount: Base Net Price = Gross Total ÷ (1 + (GST Rate ÷ 100)). GST Amount = Gross Total - Base Net Price.

What are CGST, SGST, and IGST?

In dual-GST tax systems like India, CGST (Central GST) and SGST (State GST) are split equally (50/50) on sales within the same state (intra-state). IGST (Integrated GST) applies at the full tax rate on sales between different states (inter-state).

Is the GST Calculator tool completely free?

Yes, our GST Calculator is 100% free with no account creation, no subscriptions, and unlimited usage across all devices.

100% Free • Fast • In-Browser Tax Engine

GST Calculator (Goods & Services Tax)

Accurately calculate GST inclusive and exclusive prices, CGST, SGST, IGST tax splits, compare tax slabs, and generate multi-item invoices in real-time.

Currency:

Calculation Mode

Net (Pre-Tax) Initial AmountNumbers only

₹

GST Tax Rate (%)Active: 18%

Standard GST Slabs:

Global / Custom Rate:

Tax Structure / Split

Tax Calculation Breakdown

18% GST

Net (Base) Price

Pre-tax value

₹ 10,000.00

Total GST Amount

+₹ 1,800.00

CGST (9%)₹ 900.00

SGST (9%)₹ 900.00

Total (Final Invoice Price)

₹ 11,800.00

Includes base price + calculated GST

Net: 84.7%GST: 15.3%

Calculation Formula Applied:

GST Amount = (₹ 10,000.00 * 18) / 100 = ₹ 1,800.00

Gross Total = ₹ 10,000.00 + ₹ 1,800.00 = ₹ 11,800.00

Complete Guide to Goods and Services Tax (GST) Calculation

The Goods and Services Tax (GST) is a comprehensive, multi-stage, destination-based indirect tax levied on every value addition in the supply chain of goods and services. Our free online GST Calculator is designed to simplify financial bookkeeping, invoicing, and tax compliance for business owners, accountants, e-commerce sellers, freelancers, and consumers worldwide.

What is GST and How Does It Work?

GST replaced a cascading web of indirect taxes—including Central Excise Duty, Service Tax, Additional Customs Duty, State VAT, Entry Tax, and Luxury Tax—with a unified single taxation regime. Under GST, tax is collected at every point of sale, with an Input Tax Credit (ITC) mechanism that ensures businesses only pay tax on the net value they add.

GST is categorized based on transaction jurisdiction into three core components:

CGST (Central GST)

Levied by the Central Government on intra-state supplies of goods and services (collected alongside SGST).

SGST / UTGST

Levied by State Governments or Union Territories on intra-state supplies within their local boundaries.

IGST (Integrated GST)

Levied on inter-state supplies (across state borders) and import/export activities, collected by the Centre and apportioned to states.

Dual Mode: Add & Remove GST

Seamlessly calculate gross amounts from net prices or perform reverse calculations to extract the pre-tax base cost from any retail MRP / GST-inclusive bill.

Automated CGST / SGST / IGST Splits

Eliminate manual math errors with automatic 50/50 intra-state tax splits and unified 100% inter-state IGST computations.

Multi-Item Invoice Estimator

Build full itemized bills with line-item quantities, discounts, variable tax slabs, subtotal summaries, and instant copy/print capabilities.

100% Client-Side Privacy Guarantee

All calculations are executed strictly in your web browser with zero server uploads, keeping your financial quotes and invoices completely private.

GST Calculation Mathematical Formulas Explained

Adding GST (Tax Exclusive Calculation)

When you know the pre-tax Net Amount and want to compute the GST Amount and Final Total: • GST Amount = (Net Base Price × GST Rate) ÷ 100 • Total Gross Price = Net Base Price + GST Amount Example: On a ₹10,000 service at 18% GST: GST = (10,000 × 18) ÷ 100 = ₹1,800. Total = ₹11,800.

Removing GST (Reverse / Tax Inclusive Calculation)

When you have a final GST-inclusive price and need to extract the original Base Net Price: • Base Net Price = Total Gross Price ÷ (1 + (GST Rate ÷ 100)) • GST Amount = Total Gross Price - Base Net Price Example: If a product costs ₹11,800 inclusive of 18% GST: Base Price = 11,800 ÷ 1.18 = ₹10,000. GST = ₹1,800.

Intra-State Tax Split (CGST & SGST)

When supplier and buyer are located within the same state: • CGST = GST Amount ÷ 2 (e.g., 9% on an 18% slab) • SGST = GST Amount ÷ 2 (e.g., 9% on an 18% slab).

Inter-State Tax Split (IGST)

When goods or services move across state borders: • IGST = GST Amount at the full rate (e.g., full 18% is billed as IGST).

Frequently Asked Questions

1.What is the formula to calculate GST?

To calculate GST to add: GST Amount = (Net Price * GST Rate) / 100. To remove GST from an inclusive price: Base Net Price = Gross Total / (1 + (GST Rate / 100)).

2.What are the main GST tax slabs in India?

The primary GST tax rates in India are 0% (unprocessed foods, fresh produce), 5% (essentials, transport, life-saving medicines), 12% (processed foods, business software, apparel above threshold), 18% (IT services, consulting, consumer goods), and 28% (automobiles, luxury goods, aerated drinks).

3.What is the difference between GST Inclusive and GST Exclusive?

GST Exclusive means the advertised price does not contain tax; tax will be added upon checkout. GST Inclusive means the listed price already contains the full tax liability.

4.How do I generate an itemized GST invoice with this tool?

Click on the "Itemized Invoice" tab, input your customer details, add line items with their quantities, unit rates, discount percentages, and GST rates. You can copy the invoice breakdown text or print/save as PDF immediately.

Security & Privacy

🔒256-Bit TLS Encryption

🗑️24-Hour File Deletion

🛡️GDPR & CCPA Compliant

🆓Free Forever — No Hidden Costs

1,402 users have processed files with this tool today

💡How to Use GST Calculator

Upload File

Select or drag your files into the processing box above.

Apply Settings

Customise processing options (where available) as needed.

Download Result

Wait 1-2 seconds and download your final processed file.

Key Features

✓ Add & Remove GST modes
✓ CGST, SGST & IGST tax splits
✓ Preset slabs (0%, 5%, 12%, 18%, 28%) & Custom rates
✓ Multi-item invoice generator & breakdown
✓ 100% private in-browser math

📲

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Welcome to the ultimate GST Calculator tool, designed to help business owners, freelancers, accountants, consumers, and students compute Goods and Services Tax (GST) effortlessly. Whether you need to calculate GST-inclusive gross prices, extract pre-tax base amounts from inclusive figures, or understand CGST, SGST, and IGST tax splits, our free online GST calculator delivers instant, exact calculations right in your browser.

Our GST calculator supports both standard rate slabs (0%, 3%, 5%, 12%, 18%, 28%) and custom tax percentages for any jurisdiction worldwide. In addition to single amount calculations, the tool provides an itemized multi-row invoice calculator with quantity, unit rate, and discount options, giving you a full breakdown with exportable invoice summaries.

Privacy is completely guaranteed: all calculations execute client-side via JavaScript on your own device. No financial records, invoice items, or price numbers are ever sent over a network or stored on external servers.