GSTIN Verification & Decoder
Validate any GSTIN against the official 15-character format and modulo-36 checksum, then decode the state, PAN, entity number and check character. Useful before issuing invoices or onboarding vendors.
What this covers
- Format + checksum validation (catches typos instantly)
- State code → state name mapping
- Embedded PAN extraction
- Entity number, default Z and check character
- Bulk paste support
Common questions
- How is a GSTIN structured?
- A GSTIN is 15 characters: first 2 digits = state code, next 10 = PAN of the entity, 13th = entity number for the same PAN in that state, 14th = the letter Z by default, 15th = checksum digit calculated using a modulo-36 algorithm.
- How do I verify if a GSTIN is valid?
- Two checks: (1) format, meaning 15 characters with the correct character classes per position, and (2) checksum, where you run the modulo-36 algorithm and verify the 15th digit matches. Our tool does both instantly. To check if it's ACTIVE, the GSTN portal lookup is required.
- Why is GSTIN verification important?
- Invoicing the wrong or inactive GSTIN means your buyer can't claim ITC and you may face mismatch notices. Verifying before issuing invoices catches typos and dormant registrations.
- What does each part of a GSTIN mean?
- Digits 1-2 are the state code, 3-12 are the entity's PAN, the 13th is the registration count for that PAN in the state, the 14th is "Z" by default, and the 15th is a checksum character.
- Can two businesses have the same GSTIN?
- No. Each GSTIN is unique. A single PAN can hold multiple GSTINs (one per state, or several per state for separate business verticals), but no number is shared between two entities.
About Ledgester
Ledgester is the Indian GST law, made queryable. The CGST Act, its rules, notifications and rulings, encoded into a fast, plain-English interface that professionals consult dozens of times a day. A reference tool from Ledgester.