Cosmetics + Rx, or cosmetics plus prescription: that is how the Seoul-based Korean brand COSRX explains its name. The idea behind it, the brand says, is "the best solutions for various skin problems", and COSRX builds its "prescriptions" from proven ingredients, drawing on its own research. Jun Sang Hun founded COSRX in 2013 and still runs the company, which is part of the Amorepacific group. The brand explains its slogan, Expecting Tomorrow, like this: "With skin-friendly ingredients that alleviate irritated skin, we want to provide a better tomorrow for our customers." COSRX calls itself "Friendly Derma" and writes: "From our very beginning, COSRX has prioritized genuine product efficacy and customer trust over decorative elements or promotional trends." On its Korean website it puts it more simply: gentle, low-irritation skincare for sensitive skin. The brand's symbol is Mr.RX, a character who finds the right ingredients for each skin concern. COSRX also makes some strong acid exfoliants, though, and the brand itself is clear about who they suit and who they don't.
How COSRX helps you choose: skin concern, routine step, acid strength
The first pointer is your skin concern. COSRX groups its products under six skin concerns: acne and breakouts, fine lines and wrinkles, dryness, pores and oil control, dullness and uneven tone, and redness and sensitivity. The second is the routine step. In the brand's R.T.P. routine (Ready, Target, Protect), cleanser and toner come first, then a serum or essence for your concern, and finally moisturiser and sunscreen. The third is acid strength. AHAs (glycolic and lactic acids, for example) remove dead skin cells, while BHAs (salicylic acid, for example) also clear sebum from pores. In the brand's comparison table, these two groups rate high for irritation, while PHAs and LHAs rate low; PHAs also moisturise, and LHAs help with both wrinkles and pigmentation. According to COSRX, AHAs generally suit dry, dull skin with uneven texture, while BHAs suit oily skin with uneven texture or visible pores, as well as acne-prone skin. If you are new to AHAs or have sensitive skin, the brand suggests starting with a low concentration. It advises using high-concentration AHA products at night, and wearing sunscreen during the day whenever you use AHAs.
COSRX has also mapped out an exfoliation ladder: its "Choose Your Perfect Exfoliator" chart. At the bottom is the gentle AHA/BHA Clarifying Treatment Toner for everyday use. One rung up are AHA 7 Whitehead Power Liquid and BHA Blackhead Power Liquid, which exfoliate more intensely and are used two to three times a week. At the top sits The AHA BHA PHA LHA 35 Peel: the brand calls its exfoliation "dramatic" and recommends it once a week. The idea is to choose the rung that suits you, not to use the whole ladder at once: COSRX advises against using several AHA products at the same time.
The 35 Peel is a rinse-off gel peel that combines acids from all four groups, 35% in total. It is not for everyone: because the acid concentration is extremely high, COSRX recommends it only for people already used to acid exfoliation, and only if their skin is not sensitive or compromised. Use it once a week, in the evening. Apply a generous layer to clean, dry skin, avoiding the eye area and lips; leave it on for no more than 10 minutes, then rinse off with lukewarm water, again keeping it away from the eyes and lips. After that, carry on with your usual routine: a non-exfoliating toner, serum, cream. Before first use, patch-test the peel on a small area of skin. Slight tingling may occur, but if it does not subside or gets stronger, rinse the peel off immediately. Do not use other exfoliants with it, including the AHA/BHA toner and the two Power Liquids from the ladder. According to the brand's layering guide for The RX line, retinol belongs on another day, and vitamin C and niacinamide products in the morning, since the peel is an evening treatment. Sunscreen is a must during the day: acids, the brand warns, can make skin more sensitive to the sun. The brand does not recommend this peel for pregnant or breastfeeding women. Exfoliators from other brands are in our peelings and enzyme powders section.
The 6 Peptide Skin Booster Serum: a serum in place of toner
COSRX recommends using its peptide serum instead of toner, as the first step straight after cleansing. That way, the brand explains, it absorbs best and works as a booster, enhancing the serums and ampoules you apply after it. The brand suggests two to three pumps: spread the serum over your face and pat it in gently. On the label, COSRX recommends applying it in several layers. It can be used every day, morning and evening, and according to COSRX it suits all skin types, including sensitive skin. On the label, each of the six peptides has its own job: collagen boosting and plumping; smoothing fine lines and firming; excess sebum and pore care; soothing; brightening; and, for copper tripeptide, retexturising and blemish care. Good partners for the serum, according to the brand, are vitamin C, retinol, niacinamide and hyaluronic acid products. In the same layering guide for The RX line, the serum pairs with every product listed, even the 35 Peel: on peel night, apply the serum after rinsing off the peel. Wait until the serum has fully absorbed before applying the next product. In Korea the serum has "functional cosmetic" status for wrinkle improvement and brightening. For first-step products from other brands, browse our toners and essences; for other brands' serums, see serums and ampoules.
COSRX lines: The RX, Advanced Snail, Full Fit, AHA BHA and One Step pads
On its official brand website COSRX singles out four lines, and its Korean store lists One Step pads among its lines. The RX, home to the peptide serum and the 35 Peel, is what the brand's Korean site calls its research-based derma line. Its ingredients are matched to specific skin concerns, its formulas are highly concentrated, and each product is built around a key ingredient of its own, such as six peptides, pure vitamin C, pure retinol, niacinamide or hyaluronic acid. Advanced Snail is a gentle hydrating and firming line built on snail secretion, which COSRX calls its longest-standing and most loved ingredient. Full Fit is a line with black bee propolis for nourishment and hydration. The fourth line, AHA BHA, includes that same gentle toner from the ladder, and AHA itself, in the brand's words, is "one of the signature ingredients in COSRX".
One Step pads are double-sided pads that, according to COSRX, stay moist down to the very last pad in the jar. The updated range comes in four colours: red, for pores and blemishes; green, calming, for sensitive skin; blue, moisturising; and pink, with peptides and collagen, for firmness and glow. The brand calls the red Blemish Pore Clear Pad an upgrade of the previous One Step Original Clear Pad. On that earlier pad's page, COSRX shows how to use a double-sided pad. After cleansing, swipe the embossed side over your face, avoiding the eye area: it clears away dead skin cells, sebum and impurities. Then gently pat your skin with the softer side to hydrate and smooth it. The same page says the pad can be used every day and suggests placing it on areas of concern for 1–3 minutes to melt sebum so it wipes off easily. For pads from other brands, see our toner pads section.
Rice overnight mask: the last step of your routine
Ultimate Nourishing Rice Overnight Spa Mask is a cream-type, leave-on overnight mask with rice extract; its Korean name translates as "sticky rice bouncy mask". According to COSRX, it is meant for dull, flaky, dehydrated and tired skin, and it nourishes, moisturises, softens and brightens. Apply it as the very last step, once the rest of your evening routine is done: spread a pea-sized amount over your whole face, massage it in and leave it on overnight. In its Korean instructions, the brand adds that thanks to its soft, creamy texture, the mask can be used not only overnight but also as a moisturiser in your basic skincare routine. For other brands' sleeping masks, see our overnight masks section.
