GST Number Validator
Validate any GSTIN and decode what each part of the 15-character GST number means.
GSTIN structure explained
A GSTIN (GST Identification Number) is a 15-character alphanumeric identifier. Each segment carries specific information about the taxpayer.
Frequently asked questions
What is GSTIN and who needs it?
GSTIN (Goods and Services Tax Identification Number) is a unique 15-digit identifier assigned to every GST-registered taxpayer in India. Any business with turnover above ₹40 lakhs (₹20 lakhs for services, ₹10 lakhs in special category states) must register for GST and obtain a GSTIN.
How does the GSTIN checksum work?
The 15th character of a GSTIN is a checksum computed using a mod-36 algorithm on the first 14 characters. The alphabet used is 0–9 followed by A–Z (36 characters). This allows detecting most transcription errors.
Can a business have multiple GSTINs?
Yes. A business registered in multiple states gets a separate GSTIN for each state. The PAN (characters 3–12) remains the same, but the state code (characters 1–2) and entity number (character 13) will differ.
What does character 13 (entity number) mean?
Character 13 is the entity number, indicating how many GST registrations the taxpayer has in the same state. The first registration is 1, the second is 2, and so on up to 9, then A, B, C... up to Z.
How can I officially verify a GSTIN?
Format validation is done here. For official verification (confirming the GSTIN is registered and active), use the GST portal search at gst.gov.in/services/searchtaxpayer. This confirms the legal name, address and filing status.