C.E.O. 15% Vitamin C Brightening Serum
Reviewed by SerumTruth Editorial · Updated July 2026
A well-packaged, disclosed 15% of a stable vitamin C ester for skin that finds L-ascorbic acid too sharp. The derivative carries a thinner evidence record than pure vitamin C, and you pay a prestige price for one active. On comfort and packaging it is a strong pick.
- Evidence21 / 30
Strength of the research behind the key actives
- Tetrahexyldecyl Ascorbate: moderate evidence
- Score is the average of the key actives’ evidence grades.
- Potency21 / 25
Dosed at studied levels, not fairy-dusted
- Tetrahexyldecyl Ascorbate (15%): dosed at a studied level
- Potency tracks how strongly the actives are dosed, led by the strongest, not how many there are.
- Delivery & stability16 / 20
Delivery tech + packaging that protects fragile actives
- Delivery: standard
- Packaging: airless, opaque
- Air- or light-sensitive actives (Tetrahexyldecyl Ascorbate), 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: Tetrahexyldecyl Ascorbate
- Value5 / 15
What a month of use costs vs. the category
- About $51 per month to use
- $85 for 30 ml, used about twice a day (about 0.3 ml each time), so a bottle lasts about 1.7 months
- Band: $6/month or less earns full marks, $60/month or more hits the floor.
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What’s inside
| Active | Disclosed | Dose |
|---|---|---|
| Tetrahexyldecyl Ascorbate | 15% | Studied |
15% tetrahexyldecyl ascorbate, an oil-soluble, more stable vitamin C ester, disclosed at 15%, in an opaque bottle with a pump. THD ascorbate is gentler and less pH-fussy than L-ascorbic acid, and the opaque pump suits an oil-phase active that can still oxidise. It is a single vitamin C active rather than a full antioxidant network.
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.