GSTIN Validator
Check the format and checksum of a 15-character Indian GSTIN and read the state from its code. 100% local — your number is never uploaded. Built for India.
Validate an Indian GSTIN
Format, checksum, state code, embedded PAN — all decoded locally in your browser.
A GSTIN (Goods and Services Tax Identification Number) is a 15-character code issued by the Goods and Services Tax Network (GSTN) in India. Its structure is fixed: characters 1–2 are the state code, 3–12 embed the holder's 10-character PAN, 13 is the registration count within the state, 14 is the letter Z by default, and 15 is a check character computed over the first 14 using a base-36 checksum. This tool validates the structure and recomputes that check character locally — nothing is sent to any server.
A passing GSTIN is well-formed, not necessarily active: registrations get cancelled and suspended, and only the official GST portal (gst.gov.in) can confirm live status and the registered business name. Use this tool to catch typos in invoices and vendor masters instantly, then verify status on the portal when compliance depends on it. Last verified: July 2026.
FAQ
How is the 15th check character computed?
Each of the first 14 characters is converted to a value (0–9 keep their value, A–Z map to 10–35). Values are multiplied by alternating factors 1 and 2, each product is reduced as quotient + remainder in base 36, and the check character is the base-36 value that makes the total a multiple of 36.
What do the first two digits tell me?
The GST state code — 27 is Maharashtra, 07 is Delhi, 29 is Karnataka, 33 is Tamil Nadu, and so on. A business registered in several states holds a separate GSTIN per state, all embedding the same PAN.
Why does the tool show a PAN inside the GSTIN?
Characters 3–12 are exactly the holder’s Permanent Account Number. The 4th character of that PAN reveals the entity type: C = company, P = individual, F = firm/LLP, H = HUF, T = trust.
Can I validate my whole vendor list?
Yes — batch mode accepts one GSTIN per line and returns a per-row verdict with the reason (bad length, bad state code, PAN pattern mismatch, or check-character failure), plus CSV export.
Does a valid format mean the vendor is genuine?
No. It only proves the number is internally consistent. To confirm the registration is active and matches the business name, use the "Search Taxpayer" function on gst.gov.in — that is the authoritative source.