At a glance
- CAS number
- 90-64-2
- INCI name
- Mandelic Acid
- Function
- exfoliant, antimicrobial, keratolytic, active
- Typical use level
- 0.5%–10%
- Solubility
- both
- Stable pH
- 3–4.5
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
Alpha-Hydroxy Mandelic Acid Phenylglycolic Acid 2-Hydroxy-2-Phenylacetic Acid Amygdalic Acid DL-Mandelic Acid
Compatibility
Works well with:
Niacinamide Hyaluronic Acid Salicylic Acid Glycerin Allantoin Panthenol
Use caution with:
Retinol Benzoyl Peroxide Vitamin C (L-Ascorbic Acid)
Mandelic acid is best formulated at a low pH (3.0–4.5) to maintain its free-acid, bioavailable form; buffering the pH above 5 significantly reduces exfoliant efficacy. Combining with other potent actives such as retinol or benzoyl peroxide can cause excessive irritation and is generally not recommended in the same formula. Its larger molecular size compared to glycolic acid makes it gentler and better tolerated on sensitive or darker skin tones.
Formulation notes
Mandelic acid is an alpha-hydroxy acid (AHA) derived from bitter almonds with a relatively large molecular weight (~152 Da), resulting in slower and more even skin penetration that causes less irritation than smaller AHAs like glycolic acid. It exfoliates by loosening corneocyte adhesion, improves skin texture, reduces hyperpigmentation, and has documented antimicrobial activity useful in acne-prone formulations. Formulators should ensure the pH is maintained below 4.5 for optimal activity and use appropriate photosensitivity warnings on finished products.
Related ingredients
- Azelaic AcidActive
- Glycolic AcidActive
- Lactic AcidPh Adjuster
- UreaHumectant
- Ascorbic AcidAntioxidant
- AstaxanthinAntioxidant