Kojic Acid
- Effective dose
- 1–2 %
- Evidence
- 3/5· Moderate
Last updated June 1, 2026
What it is
Kojic acid is a fungal-derived compound used to lighten areas of excess pigment. It works by chelating copper at the active site of tyrosinase, the enzyme that controls melanin production, thereby slowing the formation of new pigment.
Benefits
Helps fade melasma, freckles, age spots, and post-inflammatory hyperpigmentation, with the strongest results when combined with other agents such as hydroquinone; topical use is generally studied at about 1-2%.
When to take it
Can be used AM and/or PM as tolerated; daily broad-spectrum SPF is essential, since sun exposure undoes pigment-fading progress.
Side effects
Can cause irritation, burning, itching, redness, and occasionally contact dermatitis; for this reason cosmetic safety reviews cap it at roughly 1-2%. Pairing with daily SPF is important because unprotected UV exposure drives the pigmentation it targets.
Sources
Products containing Kojic Acid
No products in our database contain this ingredient yet.