OUAI Fine Hair Shampoo — 32 oz Biotin Thickening Shampoo for Fine, Thin Hair with Keratin & Chia Seed Oil, Sulfate-Free Volume

OUAI Fine Hair Shampoo is a salon-size, biotin-infused thickening shampoo that adds noticeable volume, strengthens strands with hydrolyzed keratin, and nourishes with chia seed oil without weighing hair down.

Designed for fine or thinning hair, this 32 oz bottle delivers a gentle, sulfate-free cleanse that builds body and reduces breakage while keeping color and chemical treatments safe. The formula combines biotin to support resilience, hydrolyzed keratin to smooth and add shine, and chia seed oil for light moisture and fuller-looking texture. The scent profile—Mercer Street—blends Italian lemon, iris, and white musk for a salon-fresh finish.

How does this shampoo create lift without leaving residue?

The lightweight formulation avoids heavy oils and silicones that flatten fine hair. Texture-enhancing ingredients deposit minimal weight at the root, so strands feel bouncy and moveable rather than stiff.

• Biotin helps improve strand strength and reduces breakage that makes hair look thinner.
• Hydrolyzed keratin smooths cuticles for reflective shine without buildup.
• Chia seed oil provides lightweight nourishment, not heaviness.
• Sulfate-free surfactants cleanse gently to preserve natural body.

Will this shampoo work on color-treated or chemically processed hair?

Yes—OUAI Fine Hair Shampoo is formulated to be safe for color, keratin, and chemically treated hair. It avoids harsh sulfates and parabens that can strip dye and compromise treatments, while supporting hair strength and surface health.

• Free of sulfates, parabens, phthalates, and gluten.
• Gentle cleansing helps preserve color vibrancy longer.
• Supports keratin-treated hair with smoothing proteins.
• Pair with OUAI Fine Conditioner to maintain volume and manageability.

How should I use it for maximum thickening effect?

Apply a palm-sized amount to wet hair, focusing on the roots, then work through to the ends and rinse thoroughly. For best results, follow with OUAI Fine Conditioner and, when desired, use OUAI Thickening Spray at the roots for extra lift.

• Massage into scalp to stimulate and build root volume.
• Rinse well to avoid any potential residue.
• Use regularly as part of a volume-focused routine.
• Combine with complementary OUAI products for layered benefits.

What sensory experience and scent can I expect?

Beyond functional benefits, the shampoo offers a refined fragrance experience—Mercer Street—with bright citrus top notes and soft floral-musky base notes. The texture feels smooth and makes hair easy to detangle after rinsing, leaving strands fresh and wearable.

• Top notes of Italian lemon for a fresh opening.
• Iris adds subtle floral sophistication.
• White musk provides a soft, long-lasting finish.
• 32 oz salon size reduces trips to reorder.

Who is this for? OUAI Fine Hair Shampoo is for people with fine, limp, or thinning hair who want a salon-quality, everyday cleanser that builds body and strengthens strands without heaviness. It suits anyone seeking color-safe, sulfate-free care—especially those who use styling products or treatments and need a dependable volume base. The large 32 oz bottle is ideal for households, salon use, or anyone who prefers fewer refills and consistent performance.