COSRX Advanced The Vitamin C 23 Serum 20g

A vitamin C serum is a targeted skincare step used to improve the appearance of dullness and uneven tone. Concentrated formulas require attention to application, storage and the other actives used alongside them. The serum complements moisturizer and daytime sunscreen; it does not replace either product.

COSRX Advanced The Vitamin C 23 Serum contains 23% ascorbic acid with additional conditioning ingredients. The Advanced formula includes glutathione, niacinamide and tocotrienols, alongside panthenol, squalane and sodium hyaluronate. This listing is for the 20g version, which the brand instructs users to refrigerate and finish within two months of opening.

23% Pure Vitamin C with Conditioning Support

The Advanced formula brings together a high concentration of pure vitamin C and a supporting blend for hydration and skin conditioning. Its identity, usage and storage instructions are distinct from treating it as a generic vitamin C serum.

• 23% ascorbic acid: The formula’s defining active is pure vitamin C at the concentration stated by COSRX. It is designed for the appearance of dullness, uneven tone and texture rather than providing makeup coverage.
• Advanced supporting blend: Glutathione, niacinamide and tocotrienols are included in this version. Tocotrienols are the ingredient associated with the brand’s Super Vitamin E wording; the full formula is listed below.
• Hydration and conditioning ingredients: Panthenol, sodium hyaluronate, squalane and allantoin accompany the vitamin C. These ingredients form part of the serum’s balanced approach to concentrated brightening care and a comfortable skin feel.
• Drop-by-drop application: COSRX recommends two to three drops over the face after cleansing and toning. Lightly shake before use, then follow with moisturizer and sunscreen during the daytime.
• Refrigerated 20g format: Storage is part of using this product correctly. Keep it at 3–10°C and use within two months of opening, rather than treating the bottle as a room-temperature, indefinite-use product.

Radiance, More Even-Looking Tone and Smoother Texture

This serum is intended for cosmetic improvements in how skin looks, including dullness and a less uniform complexion. Consistent, appropriate use includes following the storage guidance and keeping daytime sun protection in the routine.

• Brighter-looking complexion: The vitamin C-focused formula helps address a dull appearance, supporting a fresher, more radiant finish without relying on tint or reflective makeup particles.
• More even-looking tone: Targeted brightening care can help improve the appearance of uneven tone and dark spots. These are appearance-focused benefits, not a guarantee that every mark will disappear.
• Smoother-looking surface: The formula also addresses uneven texture, helping skin look more refined alongside its brightening role. It offers a focused step before moisturizer rather than a replacement for the whole routine.
• Firmer-looking skin: COSRX positions this Advanced serum for a more firm-looking appearance as part of its broader radiance and texture benefits, without requiring additional clinical claims or promised timelines.
• Conditioning alongside active care: The supporting ingredients provide moisture-focused care within the concentrated formula. Follow the brand’s pairing instructions rather than layering multiple potent products in the same application.

You Get:

• 1 × COSRX Advanced The Vitamin C 23 Serum, 20g