Finance calculators

GST Calculator

Updated Jun 3, 2026 By Jehan Wadia
GST Rate Configuration
Pick a slab above or type a custom rate (0–100%).
Enter a valid rate between 0 and 100.
Shown as a prefix on all money fields.
Enter Any One Value
GST Exclusive Price
Pre-tax / net amount.
Enter a valid amount.
GST Amount
The tax component only.
Enter a valid amount.
GST Inclusive Price
Final amount including GST.
Enter a valid amount.
Results
GST Exclusive Price
$100.00
GST Amount (10%)
$10.00
GST Inclusive Price
$110.00

Introduction

This free GST Calculator helps you quickly find the GST amount, the price before tax, or the total price after tax. GST stands for Goods and Services Tax. It is a tax added to the price of most goods and services. With this tool, you can add GST to a base price, remove GST from a total price, or work backward from just the tax amount. Simply pick a GST rate, enter any one value, and the calculator does the rest. It works with common tax slab rates like 5%, 10%, 12%, 15%, 18%, and 28%, and you can also type in any custom rate you need. The results update instantly and include a clear visual chart that shows how much of the final price is tax and how much is the actual cost.

How to Use Our GST Calculator

Enter a GST rate and any one price value below. The calculator will instantly figure out the other two values and show you a visual breakdown of the tax.

GST Rate (%): Pick a common slab rate like 5%, 10%, 12%, 18%, or 28% by clicking a button, or type any custom rate between 0 and 100 into the rate box.

Currency Symbol: Change the currency symbol if you do not use dollars. Type up to 3 characters like €, £, or ₹.

GST Exclusive Price: Enter the price before tax and click "Add GST." The calculator will add the GST on top and show you the tax amount and the final inclusive price.

GST Amount: If you only know the tax amount, type it here and click "Get Prices." The calculator will work backward to find both the pre-tax price and the total price.

GST Inclusive Price: Enter the total price that already has tax built in and click "Get GST." The calculator will split it into the base price and the GST amount for you.

Results: All three values appear in the results section along with a donut chart that shows how much of the total price is tax and how much is the actual cost.

What Is GST and How Does This Calculator Help?

GST stands for Goods and Services Tax. It is a tax added to the price of most goods and services when you buy them. The government collects this tax from businesses, and businesses pass the cost on to buyers. Many countries use GST, including India, Australia, Canada, and Singapore. Each country sets its own GST rates.

There are two main prices you will see when GST is involved:

  • GST Exclusive Price – This is the base price before any tax is added. It is also called the net price or pre-tax price.
  • GST Inclusive Price – This is the final price you actually pay. It includes the base price plus the GST amount on top of it.

The GST amount is the difference between the inclusive and exclusive prices. To find it, you multiply the exclusive price by the GST rate. For example, if an item costs $100 before tax and the GST rate is 10%, the GST amount is $10, and the total price you pay is $110.

This calculator works in three directions. You can enter any one of the three values — exclusive price, GST amount, or inclusive price — and it will figure out the other two for you. This is useful for business owners creating invoices, shoppers who want to know how much tax they are paying, or accountants who need to break down a total into its tax and pre-tax parts. If you are dealing with sales tax in the United States rather than GST, our Sales Tax Calculator is designed specifically for that purpose. You may also find our Reverse Tax Calculator helpful when you need to extract the pre-tax price from a total that already includes tax.

Common GST slab rates like 0%, 5%, 10%, 12%, 15%, 18%, and 28% are built in for quick selection. You can also type in any custom rate between 0% and 100% if your country or product uses a different rate. Business owners tracking profitability alongside tax obligations may want to use our Margin Calculator or Markup Calculator to understand how GST affects their pricing strategy. For a broader view of your tax obligations, our Income Tax Calculator and Effective Tax Rate Calculator can help you plan your overall tax burden, while the Net to Gross Calculator is useful for converting between net and gross figures in payroll or pricing contexts. If you need to understand the percentage relationship between values or calculate a discount before applying GST, those tools complement this calculator well.


Frequently asked questions

What is the difference between GST exclusive and GST inclusive price?

The GST exclusive price is the base price before any tax is added. The GST inclusive price is the final price you pay after tax is added on top. For example, if an item costs $100 before tax and GST is 10%, the exclusive price is $100 and the inclusive price is $110.

How do I add GST to a price?

Multiply the base price by the GST rate and add the result to the base price. The formula is: Inclusive Price = Exclusive Price × (1 + GST Rate ÷ 100). For example, $200 with 10% GST = $200 × 1.10 = $220.

How do I remove GST from a total price?

Divide the total price by (1 + GST rate ÷ 100). The formula is: Exclusive Price = Inclusive Price ÷ (1 + GST Rate ÷ 100). For example, $220 with 10% GST: $220 ÷ 1.10 = $200. The GST amount is $220 − $200 = $20.

Can I use a custom GST rate that is not listed?

Yes. The calculator has common slab rates as quick buttons, but you can type any rate between 0% and 100% into the GST Rate box. This lets you use whatever rate applies in your country or for your product.

How do I find the pre-tax price if I only know the GST amount?

Enter the GST amount in the GST Amount box and click Get Prices. The formula used is: Exclusive Price = GST Amount ÷ (GST Rate ÷ 100). For example, if the GST amount is $15 and the rate is 5%, the exclusive price is $15 ÷ 0.05 = $300.

Why can't I get prices from a GST amount when the rate is 0%?

When the GST rate is 0%, the tax is always zero no matter what the price is. So there is no way to work backward from a tax amount to find the price. You need a rate above 0% for this feature to work.

Can I change the currency symbol?

Yes. Type any symbol up to 3 characters in the Currency Symbol box. You can use $, , £, , or any other symbol. It will update across all fields and results automatically.

What does the donut chart in the results show?

The donut chart shows a visual split of the GST inclusive price. The blue section is the base price (exclusive price) and the green section is the GST amount. The center of the chart shows the total inclusive price. This helps you see how much of the final cost is tax.

What is the formula for calculating GST amount?

The formula is: GST Amount = Exclusive Price × (GST Rate ÷ 100). For example, if the exclusive price is $500 and the GST rate is 18%, the GST amount is $500 × 0.18 = $90.

Which countries use GST?

Many countries use GST, including India, Australia, Canada, Singapore, New Zealand, and Malaysia. Each country sets its own rates. For example, Australia uses 10%, India uses multiple slabs (5%, 12%, 18%, 28%), and Canada uses 5% for federal GST.

Is GST the same as VAT?

They work in a similar way. Both are taxes added to the price of goods and services. VAT (Value Added Tax) is the term used in Europe and many other countries, while GST is used in countries like India, Australia, and Canada. The calculation method is the same.

Can I calculate GST for multiple items at once?

This calculator handles one price at a time. To calculate GST for multiple items, add up all the prices first to get one total, then enter that total into the calculator. This works if all items share the same GST rate.

Does the calculator round the results?

Yes. All money values are rounded to two decimal places (cents). This is standard for most currency calculations and invoicing.

What GST rate should I use?

Use the rate that applies to your country and the type of product or service. For example, Australia uses 10%, India uses 5%, 12%, 18%, or 28% depending on the item, and New Zealand uses 15%. Check your local tax authority for the correct rate.

How is GST different from sales tax?

GST is applied at every stage of the supply chain, and businesses can claim credits for GST they have already paid. Sales tax is usually charged only once at the final point of sale to the consumer. The end result for the buyer is similar, but the way the tax is collected differs.