The digital field guide · 124 pages

The serum aisle, decoded.

The Skin Edition from peptides³ is a masterfully researched guide to every peptide worth knowing — what each one does, what it pairs with, and which bottles actually deliver it. Read it once and never waste money on marketing again.

4.9 from 2,300+ readersInstant PDF download30-day guarantee
Amber serum bottles arranged on a soft neutral background

GHK-Cu · carrier peptide

Signals collagen synthesis — p. 33

The peptide market runs on confusion. Brands rename the same molecule, under-dose the formula, and charge for the story. The fix isn't another serum — it's knowing how to read.

Woman applying a serum in her skincare routine
Skincare products in a flat lay arrangement

Contents · 124 pages

What's inside

Eight chapters, front to back in two evenings. Or jump straight to the routines and work backwards.

  1. 01

    The peptide primer

    What a peptide actually is, and why chain length decides everything.

  2. 02

    Signal peptides

    Matrixyl and friends — the molecules that ask your skin for more collagen.

  3. 03

    Carrier peptides

    The GHK-Cu deep dive. Why the blue serum earns its reputation.

  4. 04

    Neurotransmitter inhibitors

    Argireline and the honest truth about “Botox in a bottle.”

  5. 05

    Enzyme inhibitors

    The quiet category that protects the collagen you already have.

  6. 06

    Reading an INCI list

    Decode any ingredient label in under a minute, like a formulator.

  7. 07

    Pairings & conflicts

    What boosts what, what cancels what. Copper and vitamin C, settled.

  8. 08

    The routines

    Complete AM/PM routines by skin type and budget, ready to follow.

  9. +

    Appendix: 60 products, graded

    Every notable peptide serum on the market, scored for concentration, formulation, and price per use.

A glass dropper releasing a drop of serum
Gly–His–Lys · the copper tripeptide

The science

Written from the evidence, not the marketing.

47 studies cited

Every claim in the guide traces back to peer-reviewed research — referenced by page, so you can check our work.

Concentration thresholds

The exact percentage at which each peptide has shown results in trials, so you can spot under-dosed formulas instantly.

Zero sponsorships

No brand paid to appear in the product index. Grades are based on formulation, concentration, and price per use.

Reader notes

2,300 readers, one refrain

I've worked the counter for nine years and I'm handing this to clients. The pairing tables alone end the copper-vs-vitamin-C debate I have every week.
Dana WhitmoreLicensed esthetician, Portland
I returned a $90 serum after chapter six. The INCI chapter paid for the guide before I'd finished reading it.
Priya RamanReader since the first edition
Finally something between an influencer's hot take and a journal paper. Rigorous, but I actually finished it in two evenings.
Marcus LeeSkincare hobbyist, 4 years
Woman with glowing skin in soft morning light

From chapter three

“GHK-Cu doesn't care what the bottle costs. It only cares whether it's actually there.”

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Edition 01 · one price

The Skin Edition

$29$49launch price

  • The 124-page guide (PDF, all devices)
  • AM/PM routine cheat sheets, printable
  • Product index: 60 peptide serums, graded
  • Pairing & conflict reference tables
  • Lifetime updates to every future edition
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Before you buy

Questions, answered

Edition 02 · Also in the library

The Performance EditionBPC-157, TB-500, GH secretagogues & 20 more

See the guide

Your skin deserves better than guesswork.

One evening of reading. A lifetime of never being fooled by an ingredient list again.

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The Skin Edition