Head to head
Medik8 Crystal Retinal 6 vs Medik8 Liquid Peptides
Same comparison whichever way you searched it: Medik8 Liquid Peptides vs Medik8 Crystal Retinal 6.
The bottom lineMedik8 Crystal Retinal 6 does more across the board (it leads on brightening / tone, anti-aging), while Medik8 Liquid Peptides is the simpler, more pared-back pick.
Reach for Medik8 Crystal Retinal 6 if you want the actives; Medik8 Liquid Peptides if you want fewer ingredients doing less, gently.
Medik8 Liquid Peptides keeps clear of pregnancy-flagged actives, while Medik8 Crystal Retinal 6 carries one that is best paused in pregnancy.
Answer nine questions and the app picks between them for your skin.
Cost per use
€0.57 an applicationabout 150 uses from 30 ml
a usual amount, not a measured dose: 3-5 drops, about 0.2 ml; from €86 as read in September 2026 and a 30 ml pack.
how this is counted
About €0.57 an application, about 150 uses from 30 ml.
- a convention: no trial has measured a serum dose
- Measured or assumed: the rule, and the dose table
€0.35 an applicationabout 150 uses from 30 ml
a usual amount, not a measured dose: 3-5 drops, about 0.2 ml; from €52 as read in September 2026 and a 30 ml pack.
how this is counted
About €0.35 an application, about 150 uses from 30 ml.
- a convention: no trial has measured a serum dose
- Measured or assumed: the rule, and the dose table
Per application, Medik8 Liquid Peptides is the cheaper: €0.35 against €0.57.
Which should you pick?
Pick Crystal Retinal 6 if
- dark spots, dullness or an uneven tone are your focus
- fine lines and firmness are the goal
Pick Liquid Peptides if
- your skin is sensitive or reacts to fragrance
- you want the more affordable option
- you are pregnant or breastfeeding
What each delivers
Side by side
| Crystal Retinal 6 | Liquid Peptides | |
|---|---|---|
| Type | Serum | Serum |
| Key actives | Glycerin, Retinal, Squalane | Glycerin, Hyaluronic acid, Pro-vitamin B5 |
| Texture | A rich, cushiony cream that sinks in slowly. | A light, fast-absorbing texture that layers cleanly under the rest of your routine, with no greasy film. |
| Fragrance | Contains fragrance | None detected |
| Feeds Malassezia | 4 measured / 3 inferred | 1 measured / none inferred |
| Pregnancy | One caution | No flagged actives |
| Ingredients | 47 listed | 35 listed |
| Price | ~€86 | ~€52 |
What's in one but not the other
The two labels share 5 of the 77 ingredients between them. The actives are where they part company.
What each one adds acts on The living epidermis, The stratum corneum, Not established for Medik8 Crystal Retinal 6 and The stratum corneum, Not established for Medik8 Liquid Peptides. That is the layer each is understood to act on, not how deep it travels.
Only in Medik8 Crystal Retinal 6
Only in Medik8 Liquid Peptides
Medik8 Liquid Peptides is a different bottle only for: pro-vitamin b5, palmitoyl tripeptide-1, argireline, matrixyl synthe'6.
Which keeps longer
a tube and one light-sensitive active: the packaging is doing work here.
where this comes from
The pack form is read off the packshot; the light-sensitive actives are the base's photostability rows, sourced on each glossary page; the period after opening (not printed) is read off the maker's page, never a reseller's. Catalogue checked September 2026.
a dropper bottle and nothing on this label that light breaks; the period after opening not read yet.
Medik8 Liquid Peptides is the one to keep if you use it slowly: a dropper bottle, nothing on this label that light breaks.
Where each label stops telling you the dose
Ingredients are listed in order of how much is inside, but only down to 1%. Below that the brand may list them in any order it likes, so the bottom of a label is a set, not a ranking. These two stop being a ranking in very different places.
Medik8 Crystal Retinal 6
ordered for its first 32%
- 1Aqua (Water)
- 2Caprylic/Capric Triglyceride
- 3Glycerin
- 4Isododecane
- 5Cetearyl Olivate
- 6Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer
- 7Cetearyl Alcohol
- 8PPG-12/SMDI Copolymer
- 9Sorbitan Olivate
- 10Tocopheryl Acetate
- 11Titanium Dioxide
- 12Eclipta Prostrata Extract
- 13Cyclodextrin
- 14Squalane
- 15Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer
- 16Phenoxyethanol
- 17Melia Azadirachta Leaf Extract
- 18Hydroxypropyl Methylcellulose
- 19Sodium Hyaluronate
- 20Tetrahexyldecyl Ascorbate
- 21Rubus Chamaemorus (Cloudberry) Seed Oil
- 22Alumina
- 23Isostearic Acid
- 24Lecithin
- 25Polyglyceryl-3 Polyricinoleate
- 26Polyhydroxystearic Acid
- 27Stearic Acid
- 28Pentylene Glycol
- 29Retinal
- 30Moringa Oleifera Seed Oil
- 31Sodium Polyaspartate
- 32Climbazole
- 33Disodium EDTA
- 34Lonicera Japonica (Honeysuckle) Flower Extract
- 35Lonicera Caprifolium (Honeysuckle) Flower Extract
- 36Daucus Carota Sativa (Carrot) Seed Oil
- 37Ethylhexylglycerin
- 383-O-Ethyl Ascorbic Acid
- 39Dipteryx Odorata (Tonka) Bean Extract
- 40Hydroxyacetophenone
- 41Polysorbate 60
- 42Sorbitan Isostearate
- 43Vanilla Planifolia (Vanilla) Fruit Extract
- 44Decylene Glycol
- 451,2-Hexanediol
- 46BHT
- 47Coumarin
32 of 47 sit below the line, marked by Phenoxyethanol. Including what it is sold on: Retinal.
Medik8 Liquid Peptides
ordered for its first 54%
- 1Aqua (Water)
- 2Glycerin
- 3Butylene Glycol
- 4Palmitoyl Tetrapeptide-7
- 5Palmitoyl Tripeptide-1
- 6Copper Heptapeptide-14 Pantothenate
- 7Heptapeptide-15 Palmitate
- 8Arginine/Lysine Polypeptide
- 9Palmitoyl Tripeptide-38
- 10Carnosine
- 11Acetyl Hexapeptide-8
- 12Pentapeptide-18
- 13Palmitoyl Tripeptide-5
- 14Tetrapeptide-21
- 15Sodium Hyaluronate
- 16Inulin
- 17Alpha-Glucan Oligosaccharide
- 18Lactic Acid/Glycolic Acid Copolymer
- 19Panthenol
- 20Ethylhexylglycerin
- 21Hydroxypropyl Cyclodextrin
- 22Dunaliella Salina (Green Algae) Extract
- 23Polysorbate 20
- 24Caprylyl Glycol
- 25Citric Acid
- 26Glyceryl Caprylate
- 27Pantolactone
- 28Phenylpropanol
- 29Polyvinyl Alcohol
- 30Carbomer
- 31Potassium Sorbate
- 32Sodium Benzoate
- 33Sorbic Acid
- 34Phenoxyethanol
- 35Xanthan Gum
16 of 35 sit below the line, marked by Ethylhexylglycerin.
Below the line is not too little to work: ceramides, retinoids and peptides all act far under a percent. It means the position stops carrying information. Where the line falls is inferred from the first ingredient whose whole job is done at a fraction of a percent, so it is a close read of the label rather than a number from the formula sheet.
The molecule doing the work
Better for…
- Dark spots & uneven toneCrystal Retinal 6
- Fine lines & firmnessCrystal Retinal 6
- Dryness & dehydrationEither works
- Sensitive, reactive skinLiquid Peptides
Who each suits
- Medik8 Crystal Retinal 6
- dry, combination, oily, normal · avoid with very sensitive skin, acne-prone skin (at high strength), breastfeeding and compromised barrier
- Medik8 Liquid Peptides
- dry, combination, normal
Medik8 Liquid Peptides is the cheaper of the two (~€52 vs ~€86).
Ready to pick one?
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Common questions
Is Medik8 Crystal Retinal 6 or Medik8 Liquid Peptides better for dark spots & uneven tone?
For dark spots & uneven tone, Medik8 Crystal Retinal 6 is the stronger pick by our read of the two formulas. Medik8 Crystal Retinal 6 does more across the board (it leads on brightening / tone, anti-aging), while Medik8 Liquid Peptides is the simpler, more pared-back pick. Reach for Medik8 Crystal Retinal 6 if you want the actives; Medik8 Liquid Peptides if you want fewer ingredients doing less, gently. Medik8 Liquid Peptides keeps clear of pregnancy-flagged actives, while Medik8 Crystal Retinal 6 carries one that is best paused in pregnancy.
Which is cheaper, Medik8 Crystal Retinal 6 or Medik8 Liquid Peptides?
Medik8 Liquid Peptides is the cheaper of the two (~€52 vs ~€86).
Can I use Medik8 Crystal Retinal 6 and Medik8 Liquid Peptides together?
They are both serums, so you would normally pick one rather than layer both in the same step. You can keep both and alternate them (morning and night, or on different days) if you like variety, but you do not need two.
What the scene shows
The cross-section at the top of this page is not decoration and not a diagram of the skin in general: it places the molecules these two are sold on at the layer each is understood to act on. Medik8 Crystal Retinal 6 is placed by Glycerin (the stratum corneum), Retinal (the living epidermis), Squalane (the stratum corneum). Medik8 Liquid Peptides is placed by Glycerin (the stratum corneum), Hyaluronic acid (the stratum corneum), Pro-vitamin B5 (the stratum corneum). A layer is where an ingredient does its work, never how deep it travels, and never a claim about how well it works.
Compare it with…
41 duels are built for this serum, Celimax The Vita A Retinal Shot Tightening Booster and La Roche-Posay Hyalu B5 Suractivated Serum among them: type a name, or pick one below.