The Ordinary sells several serums with Multi-Peptide in the name, and search traffic runs them together. This one is the face formula with hyaluronic acid. It has the longest peptide list of any product analysed on this site so far, and the brand names the supplier technology behind every peptide in it, which makes the list unusually checkable.
Seven ingredients, five names
The published list runs to 51 ingredients. The peptides sit together near the top:
| Pos. | Ingredient (INCI) | Supplier name, as the brand gives it | Molecular weight | PubMed records |
|---|---|---|---|---|
| 4 | Acetyl Hexapeptide-8 | ARGIRELOX, by elimination (with pos. 5) | 887.0 g/mol | see note |
| 5 | Pentapeptide-18 | ARGIRELOX, by elimination (with pos. 4) | 569.6 g/mol | 6 |
| 6 | Palmitoyl Tripeptide-1 | Matrixyl 3000 (with pos. 7) | 578.8 g/mol | see note |
| 7 | Palmitoyl Tetrapeptide-7 | Matrixyl 3000 (with pos. 6) | 694.9 g/mol | see note |
| 8 | Palmitoyl Tripeptide-38 | Matrixyl synthe'6 | 676.0 g/mol | 3 |
| 9 | Dipeptide Diaminobutyroyl Benzylamide Diacetate | SYN-AKE | 495.6 g/mol | 1 |
| 10 | Acetylarginyltryptophyl Diphenylglycine | named in full | 668.7 g/mol | 0 |
Weights from PubChem, counts from NCBI E-utilities in titles and abstracts (INCI name or trade name), all read 2026-09-17. Where the site already keeps an evidence entry for a peptide, its census lives there: Argireline, palmitoyl tripeptide-1, palmitoyl tetrapeptide-7 and Matrixyl, which covers all three Matrixyl products.
ARGIRELOX is the one pairing to read carefully. The brand names it as a technology but does not map it to INCI names. Assign SYN-AKE, both Matrixyl products and acetylarginyltryptophyl diphenylglycine, and two peptides remain: the Argireline peptide at position 4 and the Leuphasyl peptide, pentapeptide-18, at position 5. Both are aimed at expression lines through the nerve signal to muscle. SYN-AKE, at position 9, is aimed at the same lines one step later, at the muscle receptor. Three of the seven peptides share one target, which is a design choice worth knowing before reading any claim about firmness or elasticity.
Why a label cannot name ARGIRELOX or Matrixyl at all, and why one molecule can wear several names, is covered in our guide to reading a peptide ingredient list.
What sits above the peptides
Positions 1 and 2 are water and glycerin. Position 3 is Lactococcus ferment lysate, a lysate of a lactic-acid bacterium, listed above every peptide in the formula. It is not among the brand's named key technologies in the product description, and PubMed returned 0 records for the INCI name in a title or abstract. Its position says it is present in a larger quantity than the first peptide; it does not say what it does.
The peptides are followed by sodium hyaluronate crosspolymer and sodium hyaluronate at positions 11 and 12, then allantoin, then eleven free amino acids at positions 14 to 24 — glycine, alanine, serine, valine, isoleucine, proline, threonine, histidine, phenylalanine, arginine and aspartic acid. The amino acids are the monomers peptides are made from, not peptides, and a count that included them would reach eighteen.
After those come sugars, urea and sodium PCA — a conventional humectant block — and then thickeners, solubilisers and preservatives, ending with phenoxyethanol and chlorphenesin at 50 and 51.
What each peptide's own file holds
The weight of the published record is concentrated at the top of the run. Acetyl hexapeptide-8 has the largest file of the seven, including a 60-person randomized placebo-controlled trial of periorbital wrinkles, and a Cosmetic Ingredient Review conclusion that finds it safe up to 0.005% with insufficient data above that — both set out on the Argireline entry. The two Matrixyl 3000 peptides each have a small file in which, as their entries report, no human trial tests either peptide alone.
The remaining four carry ten title-or-abstract records between them:
- Pentapeptide-18 (Leuphasyl): 6. A record count that small, for an ingredient sold in combination, means its own contribution to any product has not been separated in the indexed literature.
- Palmitoyl tripeptide-38 (Matrixyl synthe'6): 3. The human data published on it, set out on our Matrixyl entry, are open-label or multi-ingredient studies.
- SYN-AKE: 1. Its one placebo-controlled trial sits in a journal PubMed does not index, and the significant difference from placebo was forehead lines while frowning — see our SYN-AKE entry.
- Acetylarginyltryptophyl diphenylglycine (Relistase): 0 under either name. Nothing in the indexed literature describes it.
None of the seven has a published concentration on this label. Our peptide serum explainer covers what position in the list can and cannot say about amounts.
The brand's own study, as published
The product page makes one efficacy statement with a basis attached: testing showed reduced appearance of crow's feet and improved smoothness, texture, elasticity and firmness after eight weeks, with a footnote reading "Independent efficacy study performed on 30 individuals over an 8-week period."
Read on 2026-09-17, the page gives no percentages, no description of a control or vehicle arm, no measurement method and no publication. A study of thirty people using a product for eight weeks with no stated comparison can show that users' skin changed; it cannot separate the formula's effect from the hyaluronic acid and humectant block, from seasonal change, or from being in a study. That is not a criticism peculiar to this brand. It is the ordinary limit of a consumer-use design, and this page states it because the claim is the only outcome data the brand attaches to the product.
Not the hair serum, and not the copper serum
Three products in the range share most of their name, and the overlap in searches is large:
- Multi-Peptide Serum for Hair Density is a scalp formula with two peptides — biotinoyl tripeptide-1 and acetyl tetrapeptide-3 — and caffeine above both. None of this serum's seven peptides is in it. See our analysis of that formula.
- Multi-Peptide + Copper Peptides 1% Serum is the product the brand's own page points to for more advanced concerns. It is a different formula and is not analysed here.
- Multi-Peptide Lash and Brow Serum shares no peptide with this one either — see its formula analysis.
Where the evidence in the list runs out
It establishes seven peptide-class ingredients in a continuous run near the top of the list, under five supplier names, with three of the seven aimed at the same expression-line mechanism. It establishes a humectant formula around them: two forms of hyaluronic acid, eleven amino acids, sugars, urea and sodium PCA. It establishes a pH of 4.50 to 5.50 as the brand publishes it. And it establishes that most of the published research on these peptides belongs to one of them, while one has none at all.
It does not establish what the finished serum does to skin. That would take use on skin, which we have not done; a declaration of contents cannot substitute for it. Hyaluronic acid's evidence, and how much of its reputation belongs to the injected form, is set out on our peptides versus hyaluronic acid page.
Sources
- The Ordinary, Multi-Peptide + HA Serum — published ingredient list, product description, pH and efficacy footnote, theordinary.com, read 2026-09-17.
- PubChem compound records read 2026-09-17: CID 71587772 (acetyl hexapeptide-8), 10099522 (pentapeptide-18), 10231864 (palmitoyl tripeptide-1), 10078408 (palmitoyl tetrapeptide-7), 71587932 (palmitoyl tripeptide-38), 71465152 (dipeptide diaminobutyroyl benzylamide diacetate), 72942020 (acetylarginyltryptophyl diphenylglycine).
- PubMed record counts via NCBI E-utilities, titles and abstracts, INCI and trade names, run 2026-09-17.
- Cosmetic Ingredient Review conclusion on acetyl hexapeptide-8 amide and the Wang 2013 randomized trial — as cited and linked on our Argireline entry.