Niacinamide

Niacinamide is a form of vitamin B3 and one of the most widely used actives in Korean skincare. In CosIng, the official European ingredient database, it carries a single registered cosmetic function — “smoothing” the skin’s surface; everything else claimed about it comes from the brands themselves, and that is how it is quoted here.

Pick the format by its role in a routine. A serum is the most concentrated step: Anua declares 10% niacinamide, 4% tranexamic acid and 2% arbutin in its formula — for the look of dark spots, dullness and enlarged pores. A toner lays down a gentler layer right after cleansing: Medicube addresses its milky toner with niacinamide, PDRN, ceramides and peptides to hydration — explicitly including acne-prone skin. Pads add dosed application: on Numbuzin’s discs the smooth jelly side works on tone and hydration, while the gauze side gently exfoliates.

A higher percentage is not automatically better — it is more demanding: a toner or cream is the softer entry for skin new to the active, and 10% makes sense once your skin knows it. Brand directions agree: niacinamide is designed for daily use, morning and evening, and Anua explicitly calls for SPF 30+ with morning use. More on the ingredient, percentages and pairings — in the niacinamide guide.