The China Post tracking number format is usually comprised of 2 alphabetic characters, 9 numeric characters, and end with 2 alphabetic characters, "CN(on behalf of China)". But other formats are existing.
China Post tracking number format:
China Post, full name China Post Group Corporation, is the official postal service of China. The State Post Bureau of the People's Republic of China, the owner of China Post, is both a regulatory authority and government-owned enterprise. Thus, it is responsible for the regulation of the national postal industry and the management of national postal enterprises. It has 82,116 postal offices and branches, 236 mail processing centers, 39,000 transportation vehicles, 5 aircraft, 73 railway carriages, 209 automatic parcel sorting machines and 20,000 computerized postal offices, which bring convenience to people's life.
You can also track your China Post tracking number on trackingmore.com