#classification

The WHO ATC (Anatomical Therapeutic Chemical) drug classification as an API — 6,400+ codes organising every medicine into a 5-level hierarchy: anatomical main group → therapeutic subgroup → pharmacological subgroup → chemical subgroup → chemical substance. Look up any ATC code (e.g. A10BA02 → metformin, N02BE01 → paracetamol, J01CA04 → amoxicillin) with its full ancestor chain, direct children and WHO Defined Daily Doses (DDD); search drugs by name; or navigate the tree from the 14 anatomical main groups. Ideal for e-prescribing, pharmacy, clinical decision support, drug databases and health analytics.

api.oanor.com/atc-api

The North American Industry Classification System (NAICS 2022) as an API — 2,100+ industry codes in a 5-level hierarchy (sector → subsector → industry group → industry → national industry). Look up any code (e.g. 541511 → Custom Computer Programming Services) with its full ancestor chain and direct children; search industries by title (e.g. "software", "restaurant"); or navigate the tree from the 20 top-level sectors down. NAICS is the standard used by US, Canadian and Mexican statistical agencies to classify business establishments. Ideal for business classification, market research, CRM enrichment, lead segmentation and economic analysis.

api.oanor.com/naics-api