COSRX The Hyaluronic Acid 3 Serum 20ml

WHY WE CHOSE THIS

We tested 10 hyaluronic acid serums. Most used a single molecular weight that only hydrated the surface. COSRX's Hyaluronic Acid 3 Serum is the only one that uses three different molecular weights to hydrate at every layer of the skin — our tester's plumpness lasted all day. From COSRX — the clinical K-Beauty brand trusted for ingredient-first formulas.

WHO IT'S FOR

• Dehydrated skin that needs hydration at every layer, not just the surface
• Anyone who uses HA serums and still feels dry by midday
• Skin that needs a lightweight hydration boost before heavier actives

THE TEXTURE

An ultra-light, water-like serum that absorbs in seconds. No stickiness. No residue. Skin feels instantly plumper and more supple after each application.

HOW TO USE

After toning, apply 3–4 drops to face and neck on slightly damp skin. Press gently until fully absorbed. Follow with moisturizer. Use morning and evening.

THE FULL INGREDIENT STORY

• Hyaluronic Acid (3 molecular weights — surface, mid, and deep hydration)
• Sodium Hyaluronate Crosspolymer (long-lasting moisture binding)
• Panthenol (barrier support + skin comfort)
• No fragrance. No alcohol. No parabens.

WHERE THIS FITS IN YOUR ROUTINE

Step 3 of 4: Cleanse → Tone → [SERUM] → Moisturize

Pairs with: COSRX Hyaluronic Acid Intensive Cream → The Hydration Layering Duo

THE GUARANTEE

30 days. If your skin isn't visibly more plump and hydrated, email us. We refund you and recommend what will work instead. No return required.