View calculation formula
Base Price = Total ÷ (1 + Rate / 100)
GST Amount = Total − Base Price
Example: ₹11,800 ÷ 1.18 = ₹10,000 Base → GST ₹1,800
How to Check Your Bill
Extract tax from total in 3 steps
Enter Total Bill
Type the final amount you see on your invoice (e.g., ₹11,800)
Pick GST Rate
Select the tax rate (usually 18% for services, 5% for food)
See Breakup
Instantly see what was the actual price and how much tax you paid
Why Your Calculation Might Be Wrong
The '18% Trap' explained
Many people try to find the tax by simply calculating 18% of the total bill.
STOP! This gives you the wrong answer.
The Wrong Way
Total × 18%
Trying to remove 18% from ₹11,800:
Why it’s wrong: If you add 18% tax to ₹9,676, you only get ₹11,417, not ₹11,800!
The Right Way
Total ÷ 1.18
Correctly extracting GST:
Correct! ₹10,000 + 18% Tax (₹1,800) = ₹11,800. Perfect match.
How Calculation Works
Visual breakdown of the math
Let’s take the same example: Bill Amount ₹11,800 with 18% GST
The Magic Numbers for other rates:
Real Life Examples
Common scenarios you might face
🍽️ Restaurant Bill
Most restaurants charge 5% GST.
💻 Freelancer / Service
Professional services are usually 18%.
Quick Cheat Sheet: Which Rate to Pick?
| Rate | Common Items |
|---|---|
| 5% | Packaged food, Restaurant food (Non-AC/AC), Clothing (<₹1000), Footwear (<₹500) |
| 12% | Computers, Processed food, Mobiles, Umbrellas, Sewing Machines |
| 18% | Most Common. Phone bills, Internet, AC Restaurants, Insurance, Banking, Notebooks |
| 28% | Luxury cars, Air Conditioners, Cement, Aerated drinks, Betting/Gambling |
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Frequently Asked Questions
Common doubts cleared in simple English
My bill says 'GST Included', what does it mean?
It means you don't need to pay any extra tax. The price written on the tag or the final bill is the final amount. The seller has already added the tax into that price. For example, if a phone is ₹20,000 (GST Inclusive), you pay exactly ₹20,000.
Why can't I just subtract 18% from the total?
This is the most common mistake! If you have ₹118 (Total) and subtract 18% (₹21.24), you get ₹96.76. BUT, if you add 18% tax to ₹96.76, you only get ₹114.17! The math doesn't work backwards like that. You must use the reverse formula: Total ÷ 1.18.
How do I calculate the actual cost manually?
Use this simple magic number method. For 18% GST, divide your total by 1.18. For 5% GST, divide by 1.05. For 12%, divide by 1.12. The result is your actual base price. Then, subtract this from the total to find the tax amount.
Which GST rate applies to me?
It depends on what you are buying or selling. 5% is for essentials (food, cloth <₹1000). 12% is for electronics like phones and processed food. 18% is the most common rate for services (restaurants, bills, professional fees). 28% is for luxury items (cars, ACs).
Is GST Inclusive the same as MRP?
Yes, in India, the MRP (Maximum Retail Price) printed on products must be 'inclusive of all taxes'. Retailers cannot charge GST on top of the MRP.
What is the formula for reverse GST calculation?
The formula is: Base Price = Total Amount ÷ (1 + (GST Rate / 100)). For example, for a ₹11,800 item with 18% GST: 11,800 ÷ (1 + 0.18) = 11,800 ÷ 1.18 = ₹10,000.