A 10% peptide product holds 0.005% peptide
Peptide quotes almost always state the dose of the supplied solution, not the peptide. The acetyl hexapeptide-8 solution carries 0.05% peptide, so a product built on 10% of it lands at 0.005%. The number after the name is not an amino acid count either.
The prefix — tri, tetra, hexa — gives the amino acid count; the number after the name is only an INCI registry serial. The concentration gap is wider: the supplied acetyl hexapeptide-8 solution is 0.05% peptide, so dosing it at 10% leaves 0.005% peptide in the finished product.
A quote that says 5% peptide does not mean 5% peptide
Peptides rarely arrive as powder. They come dissolved — in water or glycerin, usually very dilute — and the figure written on a quote is the dose of that solution, not of the peptide inside it. "5% peptide" and "5% peptide content" end up describing different formulas.
The most widely used peptide shows how far apart. The acetyl hexapeptide-8 solution that suppliers ship carries 0.05% peptide. A product labelled "10% peptide" is built on 10% of that solution, which leaves 0.005% peptide in the finished product.
Those two numbers sit 2,000-fold apart. Compare label figures alone and the higher one reads as the stronger formula, while the quote rarely says whether the figure refers to the solution or the peptide.
| Material | Supplied as | Peptide in solution | Dose in formula | Peptide in product |
|---|---|---|---|---|
| Acetyl hexapeptide-8 | Aqueous solution | 0.05% | 2–5% suggested | 0.001–0.0025% |
| Copper tripeptide-1 (5,000 ppm) | Aqueous solution | 0.5% | 2–10% | 0.01–0.05% |
| Palmitoyl tripeptide-1 + tetrapeptide-7 | Glycerin gel | Not published | 3–8% suggested | Cannot be derived |
The third row is where sourcing usually stalls. That gel declares glycerin, water, butylene glycol, carbomer and polysorbate 20 ahead of its two peptides, and the supplier does not publish either peptide's share. What is on record is the tested level of the earlier palmitoyl pentapeptide work, around 3 ppm.
The number after the name is not an amino acid count
Read a peptide name in two halves. The prefix — tri, tetra, penta, hexa — says how many amino acids are in the chain, and the figure after the name is a serial number assigned when the ingredient was registered in INCI. Proposals still cross our desk reading hexapeptide-8 as eight peptides or eight amino acids.
| Name | Amino acids | Trailing number |
|---|---|---|
| Palmitoyl tripeptide-1 | 3 | Registry serial |
| Palmitoyl tetrapeptide-7 | 4 | Registry serial |
| Palmitoyl pentapeptide-4 | 5 | Registry serial |
| Acetyl hexapeptide-8 | 6 | Registry serial (same molecule as -3) |
| Copper tripeptide-1 | 3 | Registry serial |
That last pairing causes real trouble. Acetyl hexapeptide-8 was for a while written acetyl hexapeptide-3, and both names point at one molecule — Ac-Glu-Glu-Met-Gln-Arg-Arg-NH2. Treat the trailing numbers as different materials and a duplicate slips through when two formulas are compared.
The ingredient list will not give you the level
Korean ingredient listing lets anything at or below 1% appear in any order. Peptides sit under that line almost without exception, so their position on the label — early or late — carries no information about how much is there.
Outside data does show the real band. Acetyl hexapeptide-8 levels filed with the FDA's voluntary registry run from 0.000005% to 0.005%, and the expert panel's safe level is also 0.005%. When researchers measured finished products by LC-MS, the highest result was 42.30 µg/g, about 0.004%.
Knowing that band settles what "high-concentration peptide" has been describing. The solution dose can reach double digits; the peptide itself moves in parts per million.
A wrinkle claim in Korea needs its own file
Annex 4 of the Regulation on the Review of Functional Cosmetics sets out the ingredients that skip the data submission for a wrinkle-care claim, and it runs to four lines: retinol, retinyl palmitate, adenosine, polyethoxylated retinamide. No peptide appears.
That is not a ban. It means the shortcut is closed, so putting wrinkle-care wording on the label requires an efficacy study and a review. A proposal that reads "peptide, wrinkle care" should be answered with a request for the review file rather than a report number.
Advertising rules land in the same place. Claim wording has to be backed by substantiation held by the company, and a supplier's marketing deck does not stand in for it. To work a formula direction and its claim range together, start in the product planner.
Three lines to ask a supplier for
First, ask for the solution level and the finished-product level in one table. Once "solution dosed at 5%, peptide in solution 0.05%, peptide in product 0.0025%" is filled in, two formulas can be set side by side.
Second, ask for full INCI names. A line reading "peptide complex" or "6 peptides" cannot be compared, and requiring the registry serial on every name exposes both duplication and dilution.
Third, check what the certificate is measuring. The same figure means a different formula depending on whether the supplier's document is stated on a solution or a peptide basis. Which materials are moving, and in which direction, is tracked daily in today's ingredient signals.
In short
- A peptide percentage on a quote is usually the solution dose, not the peptide content.
- The supplied acetyl hexapeptide-8 solution is 0.05% peptide; dosed at 10% that is 0.005%.
- The prefix gives the amino acid count; the trailing number is an INCI registry serial.
- Acetyl hexapeptide-3 and -8 are two names for the same molecule.
- No peptide sits on Korea's four-ingredient wrinkle-care waiver list, so the claim needs a review file.
*Sources: solution level, FDA registry band and LC-MS results — Argireline review (Aesthetic Cosmetology and Medicine, 2021) / sequence and name history — Acetyl hexapeptide-8 (Wikipedia) / suggested dose — Argireline Amplified (Lotioncrafter) / copper tripeptide-1 5,000 ppm solution — Copper Tripeptide-1 TDS / gel composition and dose range — Matrixyl 3000 guide, tested level record. Checked 20 October 2026.*
Questions people ask
It is an INCI registry serial, not a count. The amino acids are the six named by "hexa". The same molecule was once written acetyl hexapeptide-3, so a different trailing number does not mean a different material.
No. The 10% is the dose of the supplied solution. That solution carries 0.05% acetyl hexapeptide-8, which puts the finished product at 0.005%.
It cannot. Korea lets anything at or below 1% be listed in any order, and peptides sit below that line almost without exception. The level has to come from the supplier's certificate or the formula sheet.
Not through the data-waiver route. Annex 4 of the Regulation on the Review of Functional Cosmetics lists four ingredients — retinol, retinyl palmitate, adenosine and polyethoxylated retinamide — and no peptide, so the claim needs its own efficacy study and a review.