Enter a GST number below to check two things at once: whether the number itself is valid, and whether the registration behind it is currently active. Valid and active are two different questions A GST number check has two layers, and mixing them up causes real mistakes. Validity asks: could this 15-character string be a GSTIN at all? Status asks: is the registration behind it alive today? A number can be perfectly valid in format yet belong to a cancelled registration — and an invoice against it is still a problem. Our tool answers both in one search. The checksum, explained without the maths The fifteenth character of every GSTIN is a check digit computed from the first fourteen. Each of those characters is converted to a number (0–9 stay as they are, A–Z become 10–35), the values are weighted alternately, summed, and the remainder against 36 determines what the final character must be. The practical consequence: if any single character is mistyped — a 0 read as O, an 8 entered as B — the check digit almost certainly stops matching, and the number can be declared invalid without any database lookup at all . That is why our checker validates format first and only then queries the registration record. An “invalid format” result means the string could never be a GSTIN; there is nothing to look up. If you want to see where each character sits and why, the GST number format guide walks through the structure using the example 27AAPFU0939F1ZV . What each GST status means — and what to do Quick self-checks before you even search Exactly 15 characters — no spaces, no hyphens. First two characters are digits and form a real state code (compare against the GST state code list ).

Characters 3–12 look like a PAN: five letters, four digits, one letter. If the supplier’s PAN is on file, it should match exactly — and you can pull every registration on that PAN with GST search by PAN . Character 14 is Z in virtually all current registrations. No GSTIN at hand at all? Start from the business name instead with GST search by name , or learn the fundamentals in what is a GSTIN . GST number check FAQs Not necessarily — it means the string you entered cannot be a GSTIN. The most common cause is a typo or an OCR error from a scanned invoice. Re-check each character against the source document, especially 0/O, 1/I and 8/B, and search again. Yes, in limited circumstances. A taxpayer whose registration was cancelled by the department can apply for revocation within the prescribed window, and a suspension can be lifted once the underlying issue is resolved. That is why re-checking status at the time of each transaction matters more than a one-time check. Suspended is provisional — proceedings are pending and the outcome is open. Cancelled is final unless revoked. In both cases, be cautious about accepting tax invoices; the table above sets out the practical steps for each. Speed and noise. Checksum-invalid numbers are rejected instantly without a lookup, which keeps results fast and filters out the large share of queries that are simply typos. It also means an “not found” result is meaningful: the format was fine, but no such registration exists. No. Active means the registration is live, not that compliance is perfect. Persistent non-filing tends to lead to suspension and then cancellation, so status is a good proxy over time — but for high-value relationships, ask the supplier for filing evidence as part of vendor verification .