To calculate the GST reverse (find the original price and tax amount from a GST-inclusive price), divide the total amount by 1 + ( GST Rate 100 ) 1 + ( G S T R a t e 1 0 0 ) to get the base price. Then, subtract the base price from the total amount to find the GST amount.
Reverse Charge Mechanism & Calculation
Subtracting GST:
To calculate how much GST is included in a price, just divide by 11. To calculate how much the price was before GST, just divide by 1.1. That's a lot of manual work for small-business owners to do every time they want o calculate GST—use our calculator instead.
Example
Reverse Charge Mechanism under GST is a mechanism under which the usual cycle of tax payment is reversed. Under Reverse Charge, the recipient pays to the supplier an amount exclusive of GST, the recipient then pays the GST directly to the Government. RCM is a complex concept that works in select scenarios only.
You can use the Cleartax reverse GST calculator to break down a total price into its base price and GST amount. Firstly, divide the GST-inclusive price by (1 + (GST rate/100)) to determine the base price. Lastly, subtract this value from the total price.
2. How is RCM calculated? RCM is calculated based on the applicable GST rates using the formula: (Value of Goods/Services) x (Applicable GST Rate). You can also make use of the GST calculator online to get the GST rate of the product or services.
How do you remove GST? The equation to subtract GST is slightly more complicated: First, take the GST-inclusive price and multiply that by 3. Then, divide the result by 23 and round that number to the nearest two decimal points.
Understanding GST Rate Reduction
Starting September 22, 2025, the GST Council reduced the number of tax slabs from four to two main rates: 5% merit rate for essential and priority items and 18% standard rate for most other goods and services. There is also a special 40% rate for luxury and sin goods.
The reversal is calculated using the following formula. Example: If the buyer claimed ₹50,000 as ITC on a purchase, and the supplier failed to pay GST for 2 months out of 12 months, the ITC reversal would be calculated proportionately. As a result, the buyer must reverse ₹8,333 of the claimed ITC.
Reverse Charge Rules for Business-to-Business (B2B) Transactions. When intangible services are supplied by a foreign provider to an Australian business (rather than a consumer), GST may not be charged by the overseas supplier. Instead, the reverse charge mechanism applies.
Adding 10% to the price is relatively easy (just multiply the amount by 1.1), reverse GST calculations are quite tricky:
Using reverse percentages is a way of working backwards on a percentages problem in order to find the original amount. In order to do this, we: Either add/subtract the percentage given in the problem from 100% to determine what percentage we have.
Net price = Original cost – GST
For example, if the cost of a product after GST of 18% is Rs. 118, its original cost is 118 – [100/(100 + 18%)}], which equates to Rs. 100.
Using Excel to Reverse Calculate GST
Here's how to do it: Use the Formula: To reverse calculate GST, the formula is =Total Price / (1 + GST rate). For example, if the total price is ₹118 with an 18% GST, the person would type =118 / 1.18' in Excel to find the original price of ₹100.
Subtracting VAT from a Price
Excel Formula to Remove the GST amount from a Total
If you have a GST-inclusive total and need to calculate the GST-exclusive amount (i.e., remove GST), divide the Total figure by 1.15.
To calculate GST, use the formula: GST Amount = (Original Price × GST Rate) ÷ 100.
Goods and Services Tax (GST)
GST is an additional 10% tax which applies to goods and services. GST is ordinarily included in invoices. However, you may be unsure as to whether your business also needs to provide it on quotes.
Reverse Charge means the liability to pay tax is on the recipient of supply of goods or services instead of the supplier of such goods or services in respect of notified categories of supply. There are two type of reverse charge scenarios provided in law.
Formula Behind Financial Sales Tax Reverse Calculator
The formula is: Base Price = Total Price / (1 + (Tax Rate ÷ 100)). Total Price is the tax-inclusive amount; Tax Rate is the applicable percentage. This calculation instantly gives you both the pre-tax price and the actual tax paid.
The reverse charge works as follows: It is only relevant to supplies that are subject to 5% or 20% VAT. Instead of the supplier charging VAT and accounting for output tax in box 1 of their next return, the customer makes the box 1 entry instead and therefore the supplier does not charge VAT on their sales invoice(s).