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3-O-Ethyl Ascorbic Acid

What 3-O-Ethyl Ascorbic Acid is & what it does

A stable, water-soluble vitamin C derivative that brightens, evens tone, and protects against free radicals. It resists oxidation better than pure vitamin C.

What is 3-O-Ethyl Ascorbic Acid and what does it do in sunscreen?

3-O-Ethyl Ascorbic Acid is a stable, water-soluble vitamin C derivative used as an antioxidant. In sunscreen it helps neutralize free radicals generated by UV exposure and works toward a brighter, more even-looking tone over time. Because it resists oxidation far better than pure vitamin C, it stays active longer in the bottle.

Is 3-O-Ethyl Ascorbic Acid safe?

Yes, for most people. It is a well-tolerated vitamin C derivative used at typical skincare levels, and it is generally gentler and more stable than pure ascorbic acid. As with any active, very sensitive skin may prefer a lower concentration, but it is considered a low-risk ingredient.

Is 3-O-Ethyl Ascorbic Acid a vitamin C?

Yes, it is a derivative of vitamin C. The molecule attaches an ethyl group to ascorbic acid, which makes it more stable and water-soluble while the skin can still convert it toward usable vitamin C. People often choose it over pure vitamin C specifically because it does not break down as quickly.

Does 3-O-Ethyl Ascorbic Acid clog pores?

Generally no. It is a water-soluble active used in small amounts, not an oil or wax, so it is not a typical pore-clogging ingredient. If congestion is a concern, the emollients and oils elsewhere in a formula are the more likely cause.

What else is 3-O-Ethyl Ascorbic Acid called?

On a label it appears under its INCI name, 3-O-Ethyl Ascorbic Acid. It is also commonly shortened to ethyl ascorbic acid or EAA in product marketing. All of these refer to the same stable vitamin C derivative.

Sunscreens with 3-O-Ethyl Ascorbic Acid

We rate 135 sunscreens that contain it, showing the top 10 by overall score:

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