Cholesterol (Standard) is the standard substance of Cholesterol, and it is applicable for quantitative analysis, quality control, and related research in biochemical experiments. Cholesterol is the primary sterol in mammals, accounting for approximately 20–25% of the plasma membrane structure. It plays a key role in regulating membrane fluidity, permeability, and protein function. As an endogenous agonist of estrogen-related receptor α (ERRα), cholesterol is widely involved in metabolic regulation and serves as a precursor for the synthesis of hormones and bile acids. It is commonly used in experimental models of hyperlipidemia.