Free GST Calculator Online
Add GST to a base price or reverse-calculate the base amount from a GST-inclusive price. Supports all Indian GST slabs.
About the GST Calculator
GST (Goods and Services Tax) is a comprehensive indirect tax levied on the supply of goods and services in India. This free online GST calculator helps you quickly add GST to a base price to get the total payable amount, or remove GST from an inclusive price to find the original base cost. It supports all standard Indian GST slabs — 5%, 12%, 18%, and 28% — as well as any custom rate you need.
Your inputs are auto-saved in your browser so you can revisit and recalculate without re-entering values. No data ever leaves your device.
How to Use the GST Calculator
Choose a Mode
Click Add GST if you have a base price and want the total, or Remove GST if you have an inclusive price and want the base amount.
Enter the Amount
Type the price in the Amount field. In Add GST mode this is the base/exclusive price; in Remove GST mode this is the GST-inclusive total.
Select a GST Rate
Pick 5%, 12%, 18%, or 28% from the dropdown, or select Custom and type your own percentage.
View Results
Click Calculate GST to instantly see the base amount, GST component, and final total.
Frequently Asked Questions
India has five GST rate slabs: 0% (essential items like fresh produce), 5% (basic necessities), 12% (processed foods, business class air travel), 18% (most goods and services, consumer electronics), and 28% (luxury goods, automobiles, tobacco). Some items also attract a cess on top of the 28% rate.
Multiply the base (exclusive) price by (1 + rate/100). For example, to add 18% GST to ₹1,000: Total = 1000 × 1.18 = ₹1,180. The GST component alone is ₹180.
Divide the inclusive price by (1 + rate/100). For example, to remove 18% GST from ₹1,180: Base = 1180 / 1.18 = ₹1,000. The GST component is ₹1,180 − ₹1,000 = ₹180.
Yes. Your amount, selected rate, and mode are saved to your browser's localStorage. This means they are pre-filled the next time you open this page. Nothing is sent to any server — all data stays on your device.