Free tool
GSTIN Check
Check that a GSTIN is correctly formed (format, check digit, State and holder type) as a first step before you look it up on the GST portal, one at a time or for a list of up to 200. For live registration status and filing history, use Search Taxpayer on the GST portal. Or upload your GSTR-1, GSTR-3B and GSTR-2B files to see where the figures in your returns do not match.
How this works
- Type one GSTIN, or paste or upload a list (one per line, up to 200).
- We check the 15-character pattern, the check character, the State code and the PAN structure inside the GSTIN.
- We do not check whether the registration is active, cancelled or filing on time: for that, use Search Taxpayer on the GST portal.
- Your list is checked and sent back to you. In this mode it is not stored.
- "Upload your returns" reads your GST return files in memory, compares them with each other and shows the differences. The files are not stored.
About this tool
- What it does
- Tests whether a GSTIN is correctly formed: the two-digit State code, the PAN inside it, the entity number, the letter Z and the check character. It does not look the number up anywhere.
- The rule it rests on
- A GSTIN follows the 15-character structure used by the GST portal, so a number that fails the pattern or the check character cannot belong to any registration. Whether a registration exists, is active or files on time can only be confirmed on the portal’s Search Taxpayer page, which this tool does not replace. Official source: GST portal: Search Taxpayer
- Checked on
- 10 November 2026. Where a figure the tool shows is still to be verified by our expert team, the tool says so instead of showing it.
- Next step
- Run the same test on your whole supplier list and see repeats and State mismatches in one go. Supplier GSTIN risk quick-scan