Possible GSTIN Generator & Luhn Checksum Validator
Generate syntactically valid 15-digit GSTIN numbers for any Indian state using PAN, registration entity count, and official Luhn Modulo-36 checksum validation.
D BIZ Possible GSTIN Generator
Select State, input 10-digit PAN, choose registration entity number, and instantly generate valid 15-digit GSTIN combinations with official GST Council Luhn Modulo-36 checksum.
GSTIN Parameters15-Digit Identifier
First 2 digits represent the unique state code assigned under GST law.
The 13th digit indicates the sequential number of registrations assigned to the same PAN in the same state (1 to 9, then A to Z).
Generated Possible GSTINKerala (32)
All Possible GSTIN Combinations (Registrations 1 to 9) for Kerala
Every business entity registered under PAN AABCU9603R in Kerala (32) will have one of these 9 standard numbers.
Understanding the 15-Digit GSTIN Structure in India
Digits 1 & 2 denote the Census 2011 2-digit Indian State code (e.g. 32 for Kerala, 27 for Maharashtra). Digits 3 through 12 represent the taxpayer's Permanent Account Number (PAN).
The 13th digit specifies the registration count within the same state under the same PAN (starts with 1 up to 9, then alphanumeric A through Z). Digit 14 is default set to 'Z' under GST council rules.
The 15th digit is a cryptographic checksum generated using the Luhn Modulo 36 algorithm. It mathematically verifies the preceding 14 characters to prevent typing errors during invoicing.
15-Digit GSTIN Structural Decomposition
As of September 30, 2026, an entity obtaining multiple GST registrations within the same state (such as separate business verticals or SEZ units) shares the same PAN but receives sequential 13th entity characters (e.g., '1', '2', '3').
Characters 1-2 represent State Code; 3-12 represent the taxpayer's 10-digit PAN; 13 is the sequential number of registrations within that state (1-9, A-Z); 14 is default 'Z'; and character 15 is a mathematical check character calculated using the Luhn Modulo-36 algorithm.
How to Use the Possible GSTIN Generator & Checksum Validator
Select Indian State / UT
Pick your operating state to automatically inject the 2-digit Census state code.
Enter 10-Character Business PAN
Provide the valid PAN of your company, partnership, or individual proprietorship.
Set Registration Count
Choose 1 for your first registration in the state (or 2, 3 for additional branch licenses).
Generate Valid GSTIN
The tool executes the Luhn Mod-36 checksum and outputs the complete 15-character identifier.
Key Highlights & Capabilities
Frequently Asked Questions (FAQs)
What does each digit in a 15-character GSTIN signify?
The first 2 digits represent the state code (e.g., 32 for Kerala). The next 10 characters are the entity's PAN. The 13th character indicates registration count in that state. The 14th character is always 'Z' by default. The 15th character is a checksum code.
What is the Luhn Modulo-36 checksum algorithm in GST?
The Luhn Modulo-36 algorithm is an error-detecting checksum used by the GST Network to catch single-character input errors, typos, and transpositions when taxpayers input GST numbers into software or portals.
Can this tool create a registered GSTIN on the government portal?
No. This tool generates structurally valid GSTIN combinations for testing, invoicing mockups, and validation purposes. An active legal GSTIN can only be issued by the Goods and Services Tax Department upon filing Form GST REG-01.
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D BIZ Possible GSTIN Generator
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