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GSTIN Validator
Check the format and check digit of any Indian GST number instantly.
GSTINs are 15 characters: State Code + PAN + Entity + Check Digit + Z
How to Read a GSTIN
Positions 1-2
State Code - 27 = Maharashtra, 24 = Gujarat
Positions 3-12
PAN of the business - 10-digit PAN issued by Income Tax Dept
Position 13
Entity Number - 1-9 for same PAN, A-Z for >9 entities
Position 14
Check Digit (Z) - Alphanumeric computed from first 13 chars
Position 15
Default "Z" - Always Z (reserved character)
Why Validate GSTINs?
Invalid GSTINs are the #1 cause of ITC claim rejections. A single transposed character in a supplier's GST number can block lakhs in input tax credit. Use this tool to catch format errors before they reach the GST portal - no login required, no data stored on our servers.
All validation happens in your browser. Nothing is sent to any server.
Need to Validate at Scale?
Invozen validates every GSTIN automatically during invoice processing and reconciliation.
See How Invozen Handles GSTIN Validation