At a glance
Texture — Lightweight oil
Key Active — THD ascorbate 20%
Best For — Dry or sensitive skin; vitamin C beginners
Price Tier — $$
What stands out
The Ordinary tells you exactly what this is, which is rare enough to be worth noting.
Their own product page says it "contains an oil-soluble vitamin C derivative that converts into vitamin C once applied," offering "similar benefits with less irritation potential" — and they explicitly steer experienced users toward their direct L-ascorbic acid products instead. A brand talking you down from its own product is a good sign.
20% THD ascorbate for $20 is the value benchmark in this category. Revision charges eight times that for a comparable ingredient.
The oil base suits dry skin and layers well as a final step, and the Vitamin F (essential fatty acids) supports the barrier.
Watch out for
It is a derivative. The conversion to usable vitamin C in skin is the assumption the whole product rests on, and the evidence for it is much weaker than for L-ascorbic acid.
The oil format will not suit oily or acne-prone skin.
The Ordinary flags a conflict with niacinamide in their own compatibility guidance — worth knowing if you use both.
Do not read "20%" as equivalent to 20% pure vitamin C. It is not the same molecule.
Key ingredients
🍊 Vitamin C (20% Ascorbyl Tetraisopalmitate) — brightens
⛑️ Fatty Acids — support skin barrier
Full ingredient list
Formulation Notes
An anhydrous oil suspension: no water, so no hydrolysis, so no stability problem. THD ascorbate is oil-soluble, which makes an oil base the natural home for it.
This is the cheapest honest way to buy THD ascorbate. If you have decided a derivative is right for your skin, there is very little reason to pay more for the same molecule.