HomeIngredient LibraryBenzyl Alcohol

Preservative

Benzyl Alcohol

Benzyl Alcohol is a preservative, solvent, fragrance, viscosity controlling used in cosmetic and personal-care formulation. Typical use level is 0.1%–1%. It is both-soluble. Stable in the pH 3–8 range.

At a glance

CAS number
100-51-6
INCI name
Benzyl Alcohol
Function
preservative, solvent, fragrance, viscosity controlling
Typical use level
0.1%–1%
Solubility
both
Stable pH
3–8

CAS number and synonyms are sourced from PubChem. Function, usage levels, pH and compatibility are AI-assisted formulation guidance — verify against your supplier's technical data sheet and applicable regulations before use.

Also known as

benzyl alcohol phenylmethanol benzenemethanol phenylcarbinol Benzoyl alcohol Benzenecarbinol Hydroxytoluene alpha-Toluenol Phenylmethyl alcohol (Hydroxymethyl)benzene Phenolcarbinol alpha-hydroxytoluene

Compatibility

Works well with:
Phenoxyethanol Ethylhexylglycerin Dehydroacetic Acid Potassium Sorbate Sodium Benzoate Glycerin Niacinamide Hyaluronic Acid Carbomer Xanthan Gum

Use caution with:
Oxidizing Agents Strong Acids Strong Bases Methylchloroisothiazolinone

Benzyl alcohol can oxidize to benzaldehyde and benzoic acid over time when exposed to air or oxidizing agents, reducing efficacy and potentially causing irritation. It is often used synergistically with other preservatives such as phenoxyethanol or dehydroacetic acid for broader spectrum coverage. Combination with methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) is generally avoided due to overlapping sensitization concerns.

Formulation notes

EU Cosmetics Regulation restricts Benzyl Alcohol to a maximum of 1% as a preservative; it is also a listed fragrance allergen (Annex III) requiring declaration on-label when above 0.001% in leave-on and 0.01% in rinse-off products. Generally considered safe at low preservative levels but can be a skin sensitizer at higher concentrations. Not recommended for use in products intended for infants under 3 years.

Frequently asked questions

What is Benzyl Alcohol?

Benzyl Alcohol is a preservative, solvent, fragrance, viscosity controlling used in cosmetic and personal-care formulation. Typical use level is 0.1%–1%. It is both-soluble. Stable in the pH 3–8 range.

What is Benzyl Alcohol used for?

Benzyl Alcohol is used as preservative, solvent, fragrance, viscosity controlling in cosmetic and personal-care formulations.

What is the typical use level of Benzyl Alcohol?

Benzyl Alcohol is typically used at 0.1%–1% in the finished formulation. Always confirm against your supplier's technical data sheet.

What is the CAS number of Benzyl Alcohol?

The CAS registry number for Benzyl Alcohol is 100-51-6. Its INCI name is Benzyl Alcohol.

At what pH is Benzyl Alcohol stable?

Benzyl Alcohol is generally stable in the pH 3–8 range.

What ingredients are compatible with Benzyl Alcohol?

Benzyl Alcohol works well with Phenoxyethanol, Ethylhexylglycerin, Dehydroacetic Acid, Potassium Sorbate, Sodium Benzoate, Glycerin, Niacinamide, Hyaluronic Acid, Carbomer, Xanthan Gum. Use caution when combining it with Oxidizing Agents, Strong Acids, Strong Bases, Methylchloroisothiazolinone.

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