COSRX

The Niacinamide 15 Serum

78 Reviews

• 하이하링

  Jun 27, 2025 (UTC)
  수부지Acne Skin
  Review under verification

  Review under verification

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  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 dehydrated skin, I loved how this product left my skin feeling fresh and matte without any oiliness. I used it consistently morning and evening, and I definitely noticed a reduction in blemishes and a more refined appearance around my pores. My overall complexion became clearer, and it balanced my skin's oil production perfectly, making it an ideal daily serum for summer. The lightweight water serum formula pairs well with other skincare products and absorbs well without pilling, even under makeup!

  Cons

  Given its high 15% concentration, it might be a bit irritating for those with super sensitive skin if used daily from the start. On days when my skin felt more sensitive, I experienced a slight tingling sensation, but it wasn't a major issue when I adjusted the amount used.

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• 이민주입니다

  Jun 4, 2025 (UTC)
  Dry SkinSensitive Skin

  Review under verification

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  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

  Using this, all my blemishes and acne disappeared. If you use it consistently, you can really feel your skin texture changing dramatically. It seems to speed up cell turnover, as I can see dead skin cells constantly coming off. It's fascinating. It feels like my skin barrier is getting stronger.

  Cons

  When you first start using it, you might experience some breakouts. Since it's pure vitamin, those with super sensitive skin should be especially careful. Also, it's not ideal to apply before makeup due to its rich feel and the amount of dead skin cells it brings to the surface. Makeup will definitely pill. For daytime, use just a tiny bit. I recommend using it mainly in the evening.

  Tip

  For best results, incorporate this product into your evening skincare routine. Start with a small amount and gradually increase usage as your skin adjusts. Remember to always follow up with sunscreen during the day, as vitamin treatments can increase skin sensitivity to UV rays.

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• 친근한꼬까도요55167

  May 31, 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

  I felt this product truly embodies the benefits of niacinamide. My blemishes have decreased, and my pores seem to have shrunk a bit. I'm not sure about the brightening effects though.

  Cons

  My skin became a bit dry. It was fine for my combination skin, but those with dry or normal skin types might need to use it with caution.

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• 이용용이용용

  May 28, 2025 (UTC)
  수부지Sensitive 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 definitely seems to reduce blemishes when applied before bed at night.

  Cons

  Occasionally, there's a tingling sensation, and areas with delicate skin like around the eyes and mouth can feel dry at times.

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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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• 1J

  Apr 5, 2025 (UTC)
  Normal 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

  My sudden outbreak of tiny blemishes dramatically reduced and then disappeared. They haven't really come back since.

  Cons

  I'm not sure if it's effective on skin marks. Also, it occasionally causes a tingling sensation, so caution might be needed when using it.

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• 레오나르드

  Mar 30, 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 found it helpful for blemish marks and noticed my skin becoming brighter

  Cons

  There's a slight irritation, so those with super sensitive skin should be cautious

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• 데글데글

  Mar 30, 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

  Definitely effective for managing blemishes. There's a noticeable difference in the amount of sebum that comes out when I use cleansing oil after wearing makeup on days I use this product versus days I don't. I skipped using it for a couple of days and was shocked by how much sebum came out when I cleansed. Since then, I've been using it religiously, and the excess sebum has stopped. This little wonder works hard!

  Cons

  The container is quite large compared to the actual amount of product inside. Someone might think it contains 40ml at first glance!

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• 우아한MS

  Mar 20, 2025 (UTC)
  Combination 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 have regulated sebum production, as my blemishes have noticeably cleared up. I plan to order another bottle once I finish my second one.

  Cons

  The liquid has a bit of stickiness, so your skin doesn't feel completely matte after application. However, it has effectively tackled my blemishes.

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• 가르니에

  Mar 17, 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

  I'm writing this review because I discovered an unexpected effect. # Brightening effect/Blemish care Using this product alone on the face didn't show noticeable results. However, when combined with a Vitamin C serum and applied in order, my face became significantly brighter the next day. With consistent use, it does improve acne scars. The blemish improvement effect is particularly remarkable on body skin. I recommend applying it to areas where only scars remain after healing, before using body emulsion. (For those with super sensitive skin, 'I absolutely do not recommend this method.' I've seen people's skin react badly. Even for those without sensitive skin, please use this method only 2-3 times a week. It's said to be quite stimulating for the skin.) # No pilling # Not excessively rich

  Cons

  It doesn't help at all with hydration or deep moisture. It actually feels a bit drying...? However, it's fine if you apply hydrating products (serums, creams, etc.) well.

  Tip

  If you consistently apply this before body emulsion on areas where only scars remain after blemishes or acne have healed on your body, your skin will become softer and the scars will gradually fade!