COSRX

The Niacinamide 15 Serum

107 Reviews

• elio

  Jun 27, 2025 (UTC)
  Normal SkinSensitive Skin
  Review under verification

  Review under verification

  The content is currently being reviewed by the Hwahae operations team, and the verification will be completed by the next business day (excluding weekends and holidays) from the date the review was written.

  OK

  Reviewed by The Hwahae Testers

  This review was written by The Hwahae Testers who received the product for free and evaluated it with a sense of representing Hwahae. The review is completely unbiased and honest, with no guidelines or restrictions. Reviews by The Hwahae Testers undergo the same strict verification process as regular reviews, and if they don't meet our standards, revisions will be requested.

  OK
  Pros

  It's a clear essence formula that isn't particularly harsh on the skin.

  Cons

  I'm not sure about its effectiveness yet. I'm hoping to see some results. I wish it would have a noticeable effect on brightening my complexion.

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• 해피승연맘

  Jun 26, 2025 (UTC)
  Combination SkinSensitive Skin
  Review under verification

  Review under verification

  The content is currently being reviewed by the Hwahae operations team, and the verification will be completed by the next business day (excluding weekends and holidays) from the date the review was written.

  OK

  Reviewed by The Hwahae Testers

  This review was written by The Hwahae Testers who received the product for free and evaluated it with a sense of representing Hwahae. The review is completely unbiased and honest, with no guidelines or restrictions. Reviews by The Hwahae Testers undergo the same strict verification process as regular reviews, and if they don't meet our standards, revisions will be requested.

  OK
  Pros

  As someone with combination skin, I love how this product has a water-like consistency that absorbs quickly and feels refreshingly light. Despite its high niacinamide content, it doesn't irritate my skin at all, which is fantastic!

  Cons

  After the serum absorbs, if you skip moisturizing, it can leave a white cast. So it's crucial to follow up with a hydrating step when using this product.

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• 고상한닭7934241

  May 24, 2025 (UTC)
  Combination SkinSensitive SkinAcne Skin

  Review under verification

  The content is currently being reviewed by the Hwahae operations team, and the verification will be completed by the next business day (excluding weekends and holidays) from the date the review was written.

  OK

  Reviewed by The Hwahae Testers

  This review was written by The Hwahae Testers who received the product for free and evaluated it with a sense of representing Hwahae. The review is completely unbiased and honest, with no guidelines or restrictions. Reviews by The Hwahae Testers undergo the same strict verification process as regular reviews, and if they don't meet our standards, revisions will be requested.

  OK
  Pros

  It seems to be gentle on the skin. The absorption is good, and I use it before bed.

  Cons

  I haven't seen significant results yet, so I'll need to use it more to really tell.

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• 가벼운흰뺨오리

  Apr 16, 2025 (UTC)
  Combination SkinSensitive SkinAcne Skin

  Review under verification

  The content is currently being reviewed by the Hwahae operations team, and the verification will be completed by the next business day (excluding weekends and holidays) from the date the review was written.

  OK

  Reviewed by The Hwahae Testers

  This review was written by The Hwahae Testers who received the product for free and evaluated it with a sense of representing Hwahae. The review is completely unbiased and honest, with no guidelines or restrictions. Reviews by The Hwahae Testers undergo the same strict verification process as regular reviews, and if they don't meet our standards, revisions will be requested.

  OK
  Pros

  I've been using this for about 2 months. Skin Sensitivity: As someone with extremely sensitive, acne-prone skin, I found this product to be surprisingly gentle and non-irritating. While it hasn't dramatically transformed my blemishes, I've noticed gradual improvements. Texture: The formula has a slightly rich consistency. Absorption: It absorbs well into the skin.

  Cons

  Due to its rich texture, I wouldn't particularly recommend this for those with oily skin. If you have even the slightest scratch or wound on your face, it can cause a tingling sensation.

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• 라나제이

  Apr 16, 2025 (UTC)
  Combination SkinSensitive Skin

  Review under verification

  The content is currently being reviewed by the Hwahae operations team, and the verification will be completed by the next business day (excluding weekends and holidays) from the date the review was written.

  OK

  Reviewed by The Hwahae Testers

  This review was written by The Hwahae Testers who received the product for free and evaluated it with a sense of representing Hwahae. The review is completely unbiased and honest, with no guidelines or restrictions. Reviews by The Hwahae Testers undergo the same strict verification process as regular reviews, and if they don't meet our standards, revisions will be requested.

  OK
  Pros

  It's fragrance-free, incredibly gentle, and feels wonderfully moisturizing when applied. Plus, it doesn't cause any blemishes.

  Cons

  So far, I haven't found anything disappointing about using this product.

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• mt1223

  Apr 14, 2025 (UTC)
  Combination SkinSensitive SkinAcne Skin

  Review under verification

  The content is currently being reviewed by the Hwahae operations team, and the verification will be completed by the next business day (excluding weekends and holidays) from the date the review was written.

  OK

  Reviewed by The Hwahae Testers

  This review was written by The Hwahae Testers who received the product for free and evaluated it with a sense of representing Hwahae. The review is completely unbiased and honest, with no guidelines or restrictions. Reviews by The Hwahae Testers undergo the same strict verification process as regular reviews, and if they don't meet our standards, revisions will be requested.

  OK
  Pros

  I didn't feel any irritation at all! Although I haven't been using it for long enough to notice dramatic effects, I was already using the Numbuzin Glutathione line and Nature Vitamin C ampoule. With this higher concentration, I can definitely feel the results. The texture is smooth, and unless you have very oily skin, I think the hydration and richness would suit anyone. It's a bit on the richer side for an ampoule, but it actually gives my skin a nice glow and keeps it from feeling dry, which I love. (I haven't seen any effects on dark spots yet though.)

  Cons

  I didn't experience any blemishes, and there wasn't really anything I found disappointing about it.

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• feel있게

  Apr 7, 2025 (UTC)
  Oily SkinAcne Skin

  Review under verification

  The content is currently being reviewed by the Hwahae operations team, and the verification will be completed by the next business day (excluding weekends and holidays) from the date the review was written.

  OK

  Reviewed by The Hwahae Testers

  This review was written by The Hwahae Testers who received the product for free and evaluated it with a sense of representing Hwahae. The review is completely unbiased and honest, with no guidelines or restrictions. Reviews by The Hwahae Testers undergo the same strict verification process as regular reviews, and if they don't meet our standards, revisions will be requested.

  OK
  Pros

  As someone in their 20s with oily skin, the most important factor when choosing skincare products is seeing results without irritation. In that regard, COSRX The Niacinamide 15 Serum is a product I'm truly satisfied with! From the first use, I was impressed by its refreshing feel and how quickly it absorbs into the skin. Even on sensitive days, it sinks in gently without any irritation. Most importantly, I really felt the effects of niacinamide, the key ingredient in this product. Due to my oily skin, I tend to have enlarged pores and blemish marks that linger, but with consistent use of this serum, my pores have visibly cleared up and blemish marks have significantly faded. That's why I've been using it consistently for over a year now. Personally, this product works really well for my skin. I started with a lower concentration version and have now settled on this higher concentration one. If you find it suits your skin, I'd definitely recommend trying the higher concentration. I especially want to recommend this to those with oily skin. It noticeably reduces oiliness and sebum production, resulting in less shine and an overall more even and smooth complexion. Among all the niacinamide products I've tried, this one is by far the most satisfying, and I plan to continue using it in the future!

  Cons

  Be careful when using, as any spills around the bottle opening can leave white marks!

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• 풀밭점심

  Apr 4, 2025 (UTC)
  Oily SkinAcne Skin

  Review under verification

  The content is currently being reviewed by the Hwahae operations team, and the verification will be completed by the next business day (excluding weekends and holidays) from the date the review was written.

  OK

  Reviewed by The Hwahae Testers

  This review was written by The Hwahae Testers who received the product for free and evaluated it with a sense of representing Hwahae. The review is completely unbiased and honest, with no guidelines or restrictions. Reviews by The Hwahae Testers undergo the same strict verification process as regular reviews, and if they don't meet our standards, revisions will be requested.

  OK
  Pros

  High concentration of niacinamide, yet it's gentle on the skin and absorbs beautifully!

  Cons

  While it's non-irritating, I find myself using it up quickly when layering due to the small amount in the bottle.

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• 모순관리

  Mar 25, 2025 (UTC)
  Oily SkinSensitive SkinAcne Skin

  Review under verification

  The content is currently being reviewed by the Hwahae operations team, and the verification will be completed by the next business day (excluding weekends and holidays) from the date the review was written.

  OK

  Reviewed by The Hwahae Testers

  This review was written by The Hwahae Testers who received the product for free and evaluated it with a sense of representing Hwahae. The review is completely unbiased and honest, with no guidelines or restrictions. Reviews by The Hwahae Testers undergo the same strict verification process as regular reviews, and if they don't meet our standards, revisions will be requested.

  OK
  Pros

  Among various niacinamide products (including 2%, 5%, 10%, and 20% formulations), this one offers the best balance of effectiveness with minimal irritation, making it suitable for long-term use

  Cons

  The price is on the steep side, and the packaging design makes it extremely difficult to use up the last bit of product

  Tip

  When used during the day, if you apply more than a certain amount (which you'll need to determine for your skin), it can leave a white cast similar to mineral sunscreens if you don't apply sunscreen over it. Adjusting the amount should solve this issue

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• 유디니야

  Mar 17, 2025 (UTC)
  Combination SkinSensitive SkinAcne Skin

  Review under verification

  The content is currently being reviewed by the Hwahae operations team, and the verification will be completed by the next business day (excluding weekends and holidays) from the date the review was written.

  OK

  Reviewed by The Hwahae Testers

  This review was written by The Hwahae Testers who received the product for free and evaluated it with a sense of representing Hwahae. The review is completely unbiased and honest, with no guidelines or restrictions. Reviews by The Hwahae Testers undergo the same strict verification process as regular reviews, and if they don't meet our standards, revisions will be requested.

  OK
  Pros

  As someone with super sensitive skin, I never thought I could use anything beyond hydrating and soothing products. I'm pleasantly surprised that this functional product is so gentle on my skin.

  Cons

  I don't have any major complaints. It seems like consistent use is necessary to see noticeable results.

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