What a GSTIN is made of
A GSTIN (Goods and Services Tax Identification Number) is 15 characters: 2-digit state code + 10-character PAN + 1 entity code + Z + 1 checksum. This tool checks the structure and the official checksum digit. See the GST state code list.
Frequently asked questions
What is a valid GSTIN format?
15 characters: two digits for the state code, the 10-character PAN of the business, one digit/letter for the entity number, the letter Z, and a final checksum character.
Does this confirm the business is real?
No. This validates the format and checksum only. To confirm a live registration, check the official GST portal's "Search Taxpayer" service.
What does the first part of a GSTIN mean?
The first two digits are the GST state code (for example 36 is Telangana, 27 is Maharashtra), and the next ten characters are the business's PAN.
Can I register GST with a virtual office?
Yes — a virtual office provides a valid GST address with a notarised NOC, Rent Agreement and Utility Bill. See VPOB vs APOB.