Retinal is among the best-evidenced cosmetic retinoids, and this is a careful version of it: encapsulated, disclosed and properly packaged, with a strength ladder to grow into. You pay a mid-tier price for the delivery and the stability. On evidence and formulation it earns it.
- Evidence30 / 30
Strength of the research behind the key actives
- Retinaldehyde: strong evidence
- Score is the average of the key actives’ evidence grades.
- Potency21 / 25
Dosed at studied levels, not fairy-dusted
- Retinaldehyde (0.06%): dosed at a studied level
- Potency tracks how strongly the actives are dosed, led by the strongest, not how many there are.
- Delivery & stability18 / 20
Delivery tech + packaging that protects fragile actives
- Delivery: encapsulated (protects and time-releases the active)
- Packaging: opaque tube
- Air- or light-sensitive actives (Retinaldehyde), so packaging is scored.
- Formulation8 / 10
Disclosure, active breadth, and ingredient generation
- 1 of 1 actives disclose a concentration
- 1 key active (breadth credit caps at 3)
- Current-generation or synergistic: Retinaldehyde
- Value11 / 15
What a month of use costs vs. the category
- About $26 per month to use
- $87 for 30 ml, used about once a day (about 0.3 ml each time), so a bottle lasts about 3.3 months
- Frequency is set by Retinaldehyde, which is used no more than 7x a week, so a bottle stretches further
- Band: $6/month or less earns full marks, $60/month or more hits the floor.
Tap any row to see how its score was built.
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What’s inside
| Active | Disclosed | Dose |
|---|---|---|
| Retinaldehyde | 0.06% | Studied |
A stabilised 0.06% retinaldehyde serum, the retinoid one conversion step closer to retinoic acid than retinol, so it works at a lower percentage. Medik8 encapsulates it and ships it in an opaque, air-limiting tube, which is exactly what a fast-oxidising retinoid needs. The "6" marks the strength, and the range steps up gradually so skin can build tolerance.
How it’s delivered
Air- and light-sensitive actives (vitamin C, copper peptides) lose potency fast in the wrong packaging, so delivery and the bottle are scored, not just what’s on the label.
The actives, explained
Cosmetic information for general education, not medical advice. The SerumProof score reflects our reading of publicly available research and formulation disclosures. See how scoring works.