A water-based scalp serum containing peptides and plant-derived actives designed to support hair density, strength, and scalp health.
Aqua (Water), Propanediol, Butylene Glycol, Glycerin, Caffeine, Biotinoyl Tripeptide-1, Acetyl Tetrapeptide-3, Larix Europaea Wood Extract, Pisum Sativum Extract, Scutellaria Baicalensis Root Extract, Triticum Vulgare Germ Extract, Glycine Soja Germ Extract, Trifolium Pratense Flower Extract, Camellia Sinensis Leaf Extract, Apigenin, Oleanolic Acid, Arginine, Glycine, Calcium Gluconate, Zinc Chloride, Lactic Acid, Gluconolactone, Dextran, Maltodextrin, Hydroxyethylcellulose, Xanthan Gum, Pentylene Glycol, Dimethyl Isosorbide, Polysorbate 20, Ppg-26-Buteth-26, Peg-40 Hydrogenated Castor Oil, Trisodium Ethylenediamine Disuccinate, Sodium Metabisulfite, Sodium Benzoate, Phenoxyethanol, Chlorphenesin
Guru Score
The Guru Score: every expert's verdict on a product, in one simple number.
Under the score you'll see how many experts weighed in, or "Early verdict" while only a few have. Paid takes count for half in the score.
Guru Certified means at least 6 experts, a score of 85% or more, and almost no Nays.
How we score →Mixed
14 experts · Strong agreementWhat the gurus are saying
This affordable serum earns consistent praise for keeping dry scalps hydrated through winter and supporting overall hair health, but the takes split sharply on how it feels on hair. Those with dry scalp issues and damage from heat styling find it genuinely helpful, while others report it leaves hair feeling sticky, greasy, or weighed down even in small amounts. For genuine hair loss, gurus recommend using it as an add-on to FDA-approved treatments rather than relying on it alone. Start with just a few drops on damp scalp in problem areas to see how your hair responds.
What they liked
What they flagged
The concerns the experts tie this product to, in their own words. Paid and founder takes don't count.
“It's not just for hair loss either, it helps with hair density, the appearance, the strength, the structure, even the anchoring fibers based on some of the studies.”
Doctorly, watch at 15:15
“It's very hydrating and leaves my scalp feeling not dry or flaky.”
No BS Beauty, watch at 0:30
“I don't apply it for hair density per se, but more for scalp health, and it certainly helps with your scalp from preventing it from getting dry.”
No BS Beauty, watch at 2:06
Every take we've logged from this product's reviews across YouTube. Click any row to watch the moment they said it.
Independent of what the gurus think, this is what the published research supports about the main active ingredients here.
Alpha hydroxy acids loosen the bonds holding dead cells at the surface. The evidence supports smoother texture and more even tone over time, and they can leave skin more sensitive to sun.
Peptides are short protein fragments meant to signal repair. The evidence for them is thinner than for retinoids or vitamin C, and it varies a lot by the specific peptide, so the category is more promising than proven.
A water-based scalp serum containing peptides and plant-derived actives designed to support hair density, strength, and scalp health.
The gurus are split. 6 of the 14 gurus give it their stamp of approval while 3 would skip it, which lands it in the middle at a Guru Score of 66%.
The Ordinary Multi-Peptide Serum for Hair Density holds a Guru Score of 66%. That is our read on how warmly the experts talk about it, based on the verdicts of 14 expert reviewers we have collected. At least one expert has named it a Top Pick in its category.
In their reviews, experts say The Ordinary Multi-Peptide Serum for Hair Density is good for thinning hair (2 experts), flaky dry patches (1 expert) and dandruff and flaky scalp (1 expert).
2 experts who reviewed The Ordinary Multi-Peptide Serum for Hair Density say it is. Doctorly put it this way: “It's not just for hair loss either, it helps with hair density, the appearance, the strength, the structure, even the anchoring fibers based on some of the studies.”
Lower-priced products in the same category that the experts still rate highly.
See how they stack up →Other products the same gurus have weighed in on, plus more from this brand and category.
Compare side by side →Stories where our editors dug into this product or its brand.
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