Code 39

Code 39 is a bar code format which has been standardized as ISO/IEC 16388, ANSI MH 10.8 M-1983, and ANSI/AIM BC1/1995, as well as the obsolete military standard MIL-STD-1189 (superseded by the ANSI/AIM standard).

Among its users is the comic book grader CGC, which includes bar codes of this sort in its encapsulated containers for graded comics.

Developer libraries

 * ZBar bar code reader library: cross-platform
 * zxing (Zebra Crossing) (barcode library for Java, ported to some other systems)