BHA (Salicylic): effective % & pH BHA
How much BHA (Salicylic) actually works? Here's the dosage, pH and evidence — the formulator-level read behind the % on a Korean label.
| Effective % | 0.5–2% |
|---|---|
| Optimal pH | 3.0–4.0 |
| Evidence | Strong |
| Onset | 2–4 weeks |
What the % on the label really means
0.5–2% salicylic acid is the standard range; '2%' is already the strong end for leave-on, so more isn't better for blackheads.
BHA (Salicylic) guide →How BHA (Salicylic) works →
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What is BHA and what does it do?
BHA, usually salicylic acid, is an oil-soluble exfoliant that can penetrate pores to dissolve oil and dead skin, helping refine the look of texture and blemish-prone skin. In Korean routines it's used a few times weekly, with sunscreen by day, to avoid over-exfoliating.
What is the difference between AHA and BHA?
AHAs like glycolic and lactic acid are water-soluble and work on the skin's surface to brighten and smooth, while BHA like salicylic acid is oil-soluble and gets into pores. In Korean skincare both are used sparingly, a few times weekly, always with daily sun protection.
✍️ Written & reviewed by the KoreaPlus Editorial team — dermatologist-informed, cosmetic-science researched & source-cited. Last reviewed 2026-06-21.
General educational information using cosmetic structure-function wording — not medical advice. Always patch-test new actives. © KoreaPlus.