PEG-55
AKA “Polyethylene Glycol 55, Macrogol 55”
Synthetic
Ingredient Facts
PEG-55
AKA: Polyethylene Glycol 55, Macrogol 55
Synthetic · Humectant · EWG: 4
Synthetic
Humectant
Solvent
Synthetic
Not Clean
A lightweight humectant that helps lock in moisture and keeps formulas smooth and easy to apply.
CAS #
25322-68-3
Form
Liquid
See origin →
Functions
Binding
Humectant
A moisture magnet. Pulls water from the air and deeper skin layers up to the surface to keep skin plump and hydrated.
Solvent
Dissolves other ingredients so they distribute evenly in the formula. Often the invisible "base" everything else is mixed into.
Locks In Moisture
Traditional Use
Polyethylene glycol with a molecular weight of approximately 550, developed in the early 20th century. Adopted by the cosmetics industry from the 1950s as a humectant and solvent for creating stable, hydrating formulations.
Skin Types
●all-skin-types
Best For
General
Melanin-Rich Skin
Suitable
Pregnancy & Breastfeeding Safe
Yes
PEG-55
European Commission
EU Cosmetic Ingredient Database (CosIng)
PEG-55 Castor Oil
European Commission
EU Cosmetic Ingredient Database (CosIng)
PEG-55 Hydrogenated Castor Oil
European Commission
EU Cosmetic Ingredient Database (CosIng)
PEG-55 Lanolin
European Commission
EU Cosmetic Ingredient Database (CosIng)
PEG-55 Propylene Glycol Oleate
European Commission
EU Cosmetic Ingredient Database (CosIng)
PEG-55 Stearate
European Commission
EU Cosmetic Ingredient Database (CosIng)
PEG-55 Propylene Glycol Oleate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
PEG-55 Stearate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Verified Feb 2026
Data: CosIng · EWG · CIR