GST Calculator

This free GST calculator adds GST to a price or removes GST from a total, at any rate — 5%, 12%, 18%, or 28% — showing the net amount, the GST amount, and the gross total. Whether you are a business invoicing customers, a shopper checking a bill, or an accountant reconciling figures, it takes the manual math out of Goods and Services Tax. Enter an amount, choose the rate, and pick whether to add or remove GST.

How to Use the GST Calculator

  1. Enter the amount — net price (to add GST) or gross total (to remove GST).
  2. Select the GST rate.
  3. Choose add or remove GST.
  4. Calculate — see the net, GST, and gross amounts.

GST Formulas

Add GST: GST Amount = Net × (Rate ÷ 100); Gross = Net + GST.

Remove GST: Net = Gross ÷ (1 + Rate ÷ 100); GST = Gross − Net.

For example, adding 18% GST to ₹1,000 gives ₹180 GST and a ₹1,180 total. Removing 18% GST from a ₹1,180 total gives back ₹1,000 net and ₹180 GST.

Common GST Rates

RateTypical Goods/Services
5%Essential items
12%Standard goods
18%Most services and goods
28%Luxury and sin goods

GST Inclusive vs Exclusive

A GST-exclusive price is the net amount before tax — you add GST to it. A GST-inclusive price already contains the tax — you remove GST to find the underlying net. Mixing these up is the most common error; this calculator handles both directions so the figures are always correct.

Why Use a GST Calculator?

Frequently Asked Questions

How do you calculate GST?

To add GST, multiply the net amount by the rate as a decimal and add it on. To remove GST, divide the gross total by (1 + rate ÷ 100) to get the net, then subtract for the GST.

How do I remove GST from a total?

Divide the GST-inclusive total by 1 plus the rate. For 18% GST, divide by 1.18. A ₹1,180 total becomes ₹1,000 net plus ₹180 GST.

What are the GST rates?

Common slabs are 5%, 12%, 18%, and 28%, applied to different categories of goods and services. The calculator works with any rate you enter.

What is the difference between GST inclusive and exclusive?

An exclusive price is before tax (you add GST), while an inclusive price already contains the tax (you remove GST to find the net).

Is this GST calculator free?

Yes — it is completely free, requires no signup, and adds or removes GST at any rate.