PROBLEM TYPE · INVALID_CHECK_DIGIT
That GTIN's check digit does not match its other digits
The request was refused before anything changed.
- Status
- 400
- Code
INVALID_CHECK_DIGIT- Type
https://packagepage.com/problems/invalid-check-digit
What this means
The last digit of a GTIN is computed from the digits before it. This value is fourteen digits long and the last one does not check out, so the number as sent is not a GTIN anybody has been assigned.
Why it usually happens
A single transposed pair, 34 typed as 43, is the usual one, and it is invisible to read back. A digit dropped during retyping does the same thing.
What to do
The response carries the number the first thirteen digits actually compute to. Compare that against the printed pack, and if they match, use it. We state the corrected number and never apply it: a GTIN is your identifier, not ours to rewrite.