ChemIDplus functions as a chemical database, or dictionary, for over 400,000 chemicals. Using names, synonyms, and structures, readers may search ChemIDplus for information about select chemicals of interest. Results often include educational links to National Library of Medicine resources, as well as federal and international agencies. Within the system, readers may search using ChemIDplus Lite, which is designed for simple searches, or ChemIDplus Advanced, which "helps users draw their own structures and perform similarity and substructure searches." For instance, searching Ethylene Glycol (antifreeze) returns a brief description of the chemical, including its molecular formula and weight, toxicity, names and synonyms, links to dozens of resources, and other useful information.