Polyglycerin-4 is a water-soluble oligomer of glycerin made of four linked units, used in cosmetic formulas as a humectant. It's chosen to attract moisture, support a supple feel, and stabilize light textures in everyday skincare.
Not typically evaluated for comedogenicity — no standardized rating available.
Our take
Is Polyglycerin-4 a Good Ingredient?
Good rating because it reliably boosts hydration with low irritation and good formula stability, though there’s limited direct clinical evidence beyond established humectant performance. It helps reduce tack versus simple glycerin, making it a practical hydrator in lightweight systems.
What it does
Skin Benefits
Helps maintain lasting hydration and reduces the feeling of tightness for softer, more comfortable skin. Contributes to a smoother, more supple surface.
Where you'll find it
Uses in Skincare & Cosmetics
Often included in serums, toners, and gel-cream moisturizers to improve spread and keep formulas feeling fresh. Also used in sheet mask essences for a hydrated finish.
Before you use it
Safety
Generally considered low risk for irritation and suitable for sensitive skin, but any humectant can feel tight or prickly on very compromised barriers. Patch test if easily reactive and pair with occlusives to prevent transepidermal water loss in very dry climates.