Free GST Calculator.
Built for
Business.
Employee.
Accounts.
Taxation.
Workflow!
Flowm Introduces a free GST calculator made for small businesses! You can now calculate GST with few steps without any complex math, much faster.
You can also Download our PWA app for fast calculations in just one click.
Download the appFormula used in GST Calculator
Here is the main two Formulas that we used in our tool to calculate GST & other amounts.
GST Exclusive Formula
GST Inclusive Formula
What is a GST Calculator?
A GST Calculator helps businesses and individuals calculate GST amounts instantly for GST-inclusive and GST-exclusive prices. It simplifies CGST, SGST, and IGST calculations for invoices, purchases, and tax compliance.
Know moreWhat GST Rate is suitable for your business
From 22nd September 2025, GST has been simplified into two slabs – 5% and 18% – with a special 0% rate for essentials and a 40% rate for luxury and sin goods. GST Rates Supported by the Calculator are:
| GST Rate | Category & What It Covers |
|---|---|
| 0% |
GST-Free Essentials
Essential items that are exempt from GST to keep basic
necessities more affordable. This includes selected
fresh food and other essential goods.
Fresh food
Essential goods
|
| 5% |
Everyday Essentials
A lower GST rate covering many commonly purchased
household and personal-use products. The category also
includes several essential consumer services.
Packaged food
Soaps
Medicines
Toothpaste
Milk products
Insurance:
Life and health insurance is now fully GST-exempt.
|
| 18% |
Standard Goods & Services
The standard GST rate for a wide range of regular
goods and services. It applies to many consumer products,
durable goods and other commonly used items.
Appliances
Televisions
Cement
Small cars
Rate change:
Several items that were previously taxed at higher rates
are now covered under this slab.
|
| 40% |
Luxury & Sin Goods
A higher rate introduced for selected luxury products
and “sin goods”, particularly products considered
non-essential or harmful.
Tobacco
Cigarettes
High-end cars
Luxury goods
Important:
The previous 28% GST slab has been removed for these
categories.
|
Frequently Asked Questions
Everything you need to know about calculating GST, GST-inclusive prices, GST-exclusive prices, and tax rates.
How do I calculate GST on an amount?
To calculate GST, multiply the original amount by the GST rate and divide by 100. For example, 18% GST on ₹10,000 is ₹1,800, making the total amount ₹11,800.
How do I calculate a GST-inclusive price?
A GST-inclusive price already contains GST. To find the original amount and GST component, divide the total amount by 100 + the GST rate and multiply by 100. For example, ₹11,800 including 18% GST contains ₹10,000 as the original amount and ₹1,800 as GST.
How do I remove GST from a price?
To remove GST from an inclusive price, use the formula: Original Amount = Inclusive Amount × 100 ÷ (100 + GST Rate). For an amount of ₹11,800 with 18% GST, the original amount is ₹10,000.
What is the formula for calculating GST?
The basic GST formula is: GST Amount = Original Amount × GST Rate ÷ 100. The final price including GST is the original amount plus the GST amount.
What are the common GST rates in India?
GST rates depend on the type of goods or services. Common GST slabs include 0%, 5%, 18%, and higher rates for specific categories. The applicable rate should be determined based on the relevant product or service.
What is the difference between CGST, SGST and IGST?
CGST and SGST are generally charged together on intra-state supplies, while IGST generally applies to inter-state supplies. For example, an 18% intra-state GST may consist of 9% CGST and 9% SGST.
Can I calculate GST for different GST rates?
Yes. Select the GST rate applicable to your goods or services and enter the amount. The calculator will calculate the GST component and the resulting total.
What is the difference between GST-inclusive and GST-exclusive?
A GST-exclusive amount is the price before GST is added. A GST-inclusive amount already contains GST. For example, ₹10,000 excluding 18% GST becomes ₹11,800 including GST.
How accurate is this GST calculator?
The calculator performs the mathematical calculation based on the GST rate you enter. The actual GST applicable to a transaction depends on the classification of the specific goods or services and applicable tax rules.