Free tool · Format + checksum

GSTIN validator

Enter a 15-character GST number and see how it decodes: state code, PAN, registration serial, and the official Luhn mod 36 check digit. Everything runs in your browser; nothing is uploaded.

GSTIN

What it checks

  • 15-character format: state · PAN · serial · type (Z/D/C) · check digit
  • State code matches an assigned state or union territory
  • Check digit verified with the official Luhn mod 36 algorithm

Type or paste a GSTIN to decode it: which state it belongs to, whose PAN, and whether the check digit actually holds.

This tool verifies the number's structure and checksum, not its registration status. For live verification use the GST portal or an authorised e-invoice API.

Frequently asked questions