All BlueChart cartridges are identified by a seven-digit ID code. This identification system uses the following convention:

Region (xx) codes include:

AE=Asia, East (Japan, China, Indonesia, etc.)	AF=Africa
AW=Asia, West	CA=Canada
EU=Europe (incl. all Mediterranean Sea)	PC=Pacific Ocean (Australia, New Zealand, etc.)
SA=South America	US=United States and the Caribbean

Size of coverage (z) codes include:

S	Small
R	Regular
L	Large
X	Xtra Large
J	Jumbo
B	Bathymetric