Rodan + Fields Pure C: A 10% Ascorbic Acid Serum With No Water and No Oil

Pure L-ascorbic acid is the most studied form of vitamin C in skincare, but it is also the fussiest. Dissolved in water it oxidises quickly, which is why many brands switch to gentler derivatives. Rodan + Fields, the US brand started by dermatologists Katie Rodan and Kathy Fields, took a different route with Pure C Serum, which it announced in February 2026.

The serum uses 10% pure ascorbic acid with no derivatives, and the brand describes the base as free of both water and oil, relying instead on humectants. Keeping water out is a common strategy for slowing the breakdown of ascorbic acid, and leaving out oils is meant to keep the texture light. Ulta's listing also mentions ginger-derived antioxidants in the formula.

The company's own eight-week testing is the basis for its headline numbers: 94% of participants are said to have shown less noticeable wrinkles, 90% fewer fine lines around the eyes and 82% softer skin, with smaller shares reporting plumper skin and smaller-looking pores. The brand also claims the serum doubles the skin's natural antioxidant capacity. These are company-reported results and the sample size is not given on the retail page, so read them as marketing claims.

The suggested routine is two to three drops morning and evening on clean skin, letting it dry before moisturiser, with sunscreen in the daytime. A 10% concentration is a moderate starting point for pure ascorbic acid, though anyone with reactive skin may still notice tingling.

Pure C Serum went on sale first on the brand's website and then at Ulta in late February. On Ulta it costs $90 for 1 oz (about 30 ml) and had a 4.7 out of 5 average from 1,051 reviews when we checked. We did not find an Indian retailer or rupee price, so it is not part of our rankings.