Mandelic Acid

Gentle alpha-hydroxy acid that exfoliates and brightens skin.

Also known as: INCI: Mandelic Acid; also called 2-hydroxy-2-phenylacetic acid, almond acid.

What it is

Mandelic acid is an alpha-hydroxy acid (AHA) derived from bitter almonds. It has a larger molecular size than glycolic acid, which allows it to penetrate skin more slowly and gently.

What it does

It dissolves the bonds between dead skin cells, promoting exfoliation and cell turnover. This reveals fresher skin underneath, improves texture, reduces hyperpigmentation and post-inflammatory erythema, and can help with acne and uneven tone. Its slower penetration makes it less irritating than smaller AHAs, making it suitable for sensitive or reactive skin.

The evidence

Strong clinical evidence supports its efficacy for exfoliation, brightening, and treating acne and melasma. Multiple peer-reviewed studies confirm it is gentler than glycolic acid while remaining effective, with good tolerability in sensitive populations.

Best for

Sensitive skin, reactive skin, darker skin tones (lower irritation risk), and those seeking gentle exfoliation with brightening and anti-acne benefits.

Pairs well with

Niacinamide, azelaic acid, vitamin C, hyaluronic acid, and gentle hydrators. Works well in layered routines with other actives when introduced gradually.

Use cautiously with

Other strong exfoliants (retinoids, high-dose glycolic or salicylic acid) in the same routine; benzoyl peroxide may reduce efficacy. Use cautiously with vitamin A derivatives until skin is acclimated.

Cautions

May cause mild irritation, redness, or dryness during adjustment; start low (5–10%) and increase frequency gradually. Increases sun sensitivity—daily SPF 30+ is essential. Avoid during pregnancy unless under medical supervision. Not recommended for active eczema or severe dermatitis.