Sodium Benzoate (Sodium Benzoate) is the inactive salt of benzoic acid, renowned for its role as a preservative in cosmetic formulations. When dissolved in water, it converts to its active form, benzoic acid, particularly effective at lower pH levels. While showing some antimicrobial activity, especially as an anti-fungal, benzoic acid's effectiveness peaks at pH 3, making it essential to consider the pH of the final product for optimal preservation. This ingredient is not considered a broad-spectrum preservative and is best used in conjunction with other preservatives, such as Potassium Sorbate, to create a synergistic effect against yeasts and molds, particularly in low pH environments. While it serves as a component in effective preservation strategies, understanding its limitations and conditions for efficacy is crucial for developers in the cosmetic industry.