GSTIN CheckSum Digit Logic

Its always an adventure for a Professional to find & acquires the information which are lesser-known to generals.

Each taxpayer is assigned a state-wise PAN-based 15-digit Goods and Services Taxpayer Identification Number (GSTIN).

Here is a format break-down of the GSTIN:

The first two digits represent the state code as per Indian Census 2011.
The next ten digits will be the PAN number of the taxpayer
The thirteenth digit will be assigned based on the number of registration within a state
The fourteenth digit will be Z by default
The last digit will be for check code. It may be an alphabet or a number.

Lets have a Detailed View of Last Digit

And Know How to Calculate this Digit

Each Digit 0-9 is awarded with a weight from 0-9
& Each Alphabet {A-Z} have weight from 10 -35

Step I - Assign Weight to Each Digit of GSTIN seperately

Step II - Assign "Place Value Factor(PVF)"
1 for All Odd Place Value
2 for All Even Place Value

Step III - Multiple Each Weight by its [PVF].

Step IV - Divide Value got in {Step III} by 36
You will get a Quotient & Remainder.

Step V - Add the Quotient & Remainder. Let this total be "A1"

Step VI - Now Do same process for all remaining GST Digit

Now Divide the Total of all "A1" by 36
And subtract the remainder from 36 itself. The Answer will be the Weight of Final Digit.

I tried with a by taking a dummy PAN

And the Solution in a Excel Sheet will look as

Friends, I tried my level best to help you with this CheckSum Digit.
For any query / suggestion , please feel free to contact me by commenting mailing me @ gauravj75@gmail.com


Thank You