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Tokkucal

GST Calculator

Work out GST exclusive and GST inclusive amounts in seconds. Enter any base amount or total, pick a standard slab (0%, 5%, 12%, 18%, 28%) or a custom rate, and see the base amount, GST amount and total price broken down clearly.

GST Rate
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About the GST Calculator

How to Use

  1. Choose Add GST if you have an amount before tax, or Remove GST if you have a final price that already includes GST.
  2. Enter the amount.
  3. Pick a common GST rate (0%, 5%, 12%, 18%, 28%) or type a custom percentage.
  4. Press Calculate to see the base amount, GST amount and total.

Formula

GST Exclusive (adding GST to a base amount):

GST = Amount × GST% ÷ 100
Total = Amount + GST

GST Inclusive (extracting GST from a total):

Base Amount = Total × 100 ÷ (100 + GST%)
GST = Total − Base Amount

Example

An item costs ₹1,000 before tax, with 18% GST applied:

GST = 1000 × 18 ÷ 100 = ₹180
Total = 1000 + 180 = ₹1,180

Detailed Explanation

Goods and Services Tax (GST) is applied at different rates depending on the category of goods or services in India, with 0%, 5%, 12%, 18% and 28% being the most common slabs. Businesses issuing invoices typically add GST to a base price (exclusive calculation), while a shopper looking at a price tag that already includes tax often needs the reverse (inclusive calculation) to see the pre-tax price.

Frequently Asked Questions

What is the difference between GST exclusive and GST inclusive?

GST exclusive means the amount you enter does not yet include GST, and the calculator adds it. GST inclusive means your amount already includes GST, and the calculator extracts the base price and GST portion from it.

What GST rate should I use?

The applicable GST rate depends on the goods or service category, most commonly 5%, 12%, 18% or 28% in India. Check your invoice or the official GST rate schedule if you are unsure.

Can I use this for a custom GST percentage?

Yes. Enter any percentage in the GST rate field — the common rate buttons are just a shortcut for the most frequently used slabs.