Ingredient dictionary

Propylene Glycol

Also listed as: 1,2-Propanediol

Propylene Glycol is a colorless, slightly syrupy liquid that attracts water and is mainly used to hydrate, dissolve ingredients and help products spread. It is on the label of 207 products in our library. Checked against our library November 6, 2026.

What Propylene Glycol does

Draws water into skin and hair
Helps dissolve other ingredients
Helps products spread evenly
Helps some preservatives work better

Propylene glycol is a synthetic liquid made from propylene oxide, a building block from the petrochemical industry. It is colorless, nearly odorless, and slightly thick, like a light syrup. Formulators have used it in cosmetics for decades, and you will often see it in shampoos, moisturizers, sunscreens, mascaras and cleansers.

In a formula, it does several jobs. It is a humectant, meaning it attracts water, so it helps skin and hair stay hydrated. It also works as a solvent, helping other ingredients blend, and some preservatives perform better alongside it. On skin, it feels light and slightly slippery rather than greasy.

Good for

Suits most skin and hair types, and is found in everyday products like moisturizers, cleansers and shampoos.

Frequently asked questions

Is propylene glycol safe in skincare?

Propylene glycol is widely considered safe in cosmetics at normal use levels. Most people tolerate it well. A few people with very sensitive or broken skin may notice stinging, and rarely someone is allergic to it. If a product stings, stop using it.

Is propylene glycol the same as antifreeze?

Not quite. Car antifreeze usually contains ethylene glycol, a different chemical that is not used in cosmetics. Propylene glycol is a related but separate ingredient, and it is used in cosmetics and some foods. Both are glycols, so the names look alike.