Purified water — the base solvent in nearly every skincare formula, often the largest-portion ingredient.
Appears first on the ingredient list of almost every water-based product — this is normal and not a sign of low quality, it simply reflects water as the main solvent.
Purified water acts as the main solvent in cosmetics, dissolving water-soluble ingredients and forming the base of a formulation. The water used is purified and deionized (almost all mineral ions removed) to improve product stability.