Peptides in skincare — what they do

Peptides are signal ingredients formulated to support a firmer, bouncier-looking complexion — a fast-growing K-beauty category.

11 peptides in the K-beauty INCI decoder

• Acetyl Tetrapeptide-5 — A peptide often used around the eyes that helps the area look less puffy and smoother.
• Argireline (Acetyl Hexapeptide-8) — A peptide that helps soften the look of expression lines for a smoother-appearing surface.
• Copper Peptide (GHK-Cu) — A copper-bound peptide that supports the look of firmer, smoother skin and helps maintain a healthy barrier.
• EGF (Epidermal Growth Factor) — A lab-made signaling protein included to support the look of refreshed, conditioned, resilient-appearing skin.
• Hexapeptide-9 — A peptide that supports the look of bouncy, firm skin and a smoother surface.
• Matrixyl (Pal-KTTKS) — A well-known peptide that supports smoother, firmer-looking skin and helps reduce the appearance of fine lines.
• Palmitoyl Tripeptide-1 — A messenger peptide that supports the appearance of firmness and helps smooth the look of fine lines.
• Palmitoyl Tripeptide-5 — A peptide that supports a plumper, firmer-looking complexion and helps soften the appearance of lines.
• Recombinant Growth Factor Protein — A bioengineered protein included to support the appearance of healthy-looking, well-conditioned skin.
• SYN-AKE Peptide — A peptide that helps relax the look of fine expression lines for a smoother appearance.
• Tripeptide-1 — A small peptide that supports the appearance of firmness and overall skin conditioning.

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✍️ 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.