Goods being imported and exported from the United States are classified using the Harmonized Tariff Schedule (HTS). Almost all countries use tariff classification systems based on this international Harmonized System (HS). The HS is defined to the six-digit level, so foreign tariff schedules will be identical with the HTS through the six-digit level but may differ at finer levels of detail.
For goods exported from the United States, statistics are initially collected and compiled in terms of approximately 8,000 commodity classifications in Schedule B: Statistical Classification of Domestic and Foreign Commodities Exported from the United States. Schedule B is based on HS.
Codes can be looked up online at these sites:
HTS
Schedule B
