GSTIN validator and format checker
A GSTIN carries its own check digit, which means a mistyped one can be caught without contacting anybody. This checks the structure and that digit, tells you the state and the PAN inside it, and sends nothing anywhere.
What the check digit proves
The fifteenth character is computed from the first fourteen using a modulo-36 algorithm. If it does not match, the number has been mistyped — which catches transposed characters, the commonest error, instantly.
What it cannot tell you
Whether the registration is active, cancelled or suspended. Only the GST portal knows that. A structurally valid GSTIN belonging to a cancelled registration will pass this check and still cost your customer their input credit.
Nothing leaves your browser
The validation runs entirely in the page using the same algorithm tBiz uses on every party master. No GSTIN you type here is transmitted, logged or stored.
GSTIN validation questions
Does this check whether the GSTIN is registered and active?
No. It verifies the structure and the check digit offline, which catches typing errors. Whether a registration is currently active is a question only the GST portal can answer, and a cancelled registration will still pass a structural check.
Is my GSTIN sent anywhere?
No. The calculation happens in your browser using the same algorithm the product uses internally. Nothing is transmitted, logged or stored, and there is no tracking script on this page.
What does the check digit catch?
Almost all single-character errors and transpositions — which is to say, almost all the ways a fifteen-character number gets copied wrong off a certificate.
Can I tell whose GSTIN it is?
Not from the number alone. You can read off the state and the PAN it contains, which is often enough to confirm that a GSTIN belongs to the entity you think it does.
Related
Validate every party once, at setup
tBiz checks the format and the check digit when you save a customer, not when you are mid-invoice.