GSTIN Validator & Decoder
Paste a GST number to validate its 15-character structure and decode the state, the embedded PAN, and the entity type — instantly, no sign-up.
A GSTIN is 15 characters: 2-digit state code · 10-char PAN · entity number · 'Z' · a checksum. This tool validates the structure and decodes it instantly. It does not query the GST portal for live active/cancelled status.
OnGravy validates your vendors' GSTINs as you onboard them and flags mismatches before they block your input tax credit at GSTR-2B matching time.
Try OnGravy →How a GSTIN is built
A GSTIN is State code (2) + PAN (10) + Entity number (1) + "Z" (1) + Checksum (1). Because the PAN sits inside it, the GSTIN ties a registration to a specific business and state — which is why a format-valid GSTIN still needs a live active-status check before you rely on it for input tax credit.
Frequently asked
A valid GSTIN is exactly 15 characters: a 2-digit state code, a 10-character PAN, a 1-character entity number, the letter Z, and a checksum character. This tool checks that structure and decodes the state and PAN for you.
Positions 1–2 are the state code, 3–12 are the PAN of the business, 13 is the registration number for that PAN in the state, 14 is a default "Z", and 15 is a checksum. So a GSTIN literally contains the PAN of the entity.
No — this validates the format and decodes it offline. Confirming that a registration is currently active (vs cancelled) requires a live GST-portal lookup. Always verify active status before claiming input tax credit on a supplier.
Yes — for a regular registration the PAN is characters 3 to 12 of the GSTIN. This tool extracts it (and skips special TDS/UIN registrations that aren't PAN-based).