Effectiveness:very effective in lighting my scars!Texture:runny serum but not sticky when it dries on your faceFragrance:c23 serum smells a bit more funky than the c13 serum100% recommending this if you want to lighten scars and brighten complexion! This is my 2nd bottle of cosrx vitamin c serum. I purchased the milder vitamin c13 serum on my 1st bottle and so far it brightened my face and lightened my acne scars. I even use it on my body acne marks and chicken pox marks and you can see it really lightened in a month or two😭 these scars are years already btw! Pur hased the more concentrated version on my second bottle so far my face isn't recating negatively yet. I use vitamin serum every after washing my face in the morning, followed by snail mucin essence and ... MoreEffectiveness:very effective in lighting my scars!Texture:runny serum but not sticky when it dries on your faceFragrance:c23 serum smells a bit more funky than the c13 serum100% recommending this if you want to lighten scars and brighten complexion! This is my 2nd bottle of cosrx vitamin c serum. I purchased the milder vitamin c13 serum on my 1st bottle and so far it brightened my face and lightened my acne scars. I even use it on my body acne marks and chicken pox marks and you can see it really lightened in a month or two😭 these scars are years already btw! Pur hased the more concentrated version on my second bottle so far my face isn't recating negatively yet. I use vitamin serum every after washing my face in the morning, followed by snail mucin essence and sun screen. I also put sunscreen on my body when I apply vitamin C. Better to store in the fridge to keep from oxidizing!!

Brightened skin!

Even in my thirties, I still have moments of mild acne breakouts which can be frustrating. I do tend to have more sensitive skin which also leads to breakouts, and it can take a bit longer to heal and resolve completely. I loved using the Vitamin C 23 serum, especially in conjunction with the Cosrx Niacinamide 15. The combination together was so effective for my skin! My face was glowing and my skin felt so hydrated and smooth. I have been applying these to my skin at night for the past month and Im truly amazed at the transformation of my skin texture and appearance. I do not use these in my morning routine. I had no sunburn, dryness or congestion issues whilst using these products. Any acne I experience was minimal and resolved quicker than normal. When you first ... MoreEven in my thirties, I still have moments of mild acne breakouts which can be frustrating. I do tend to have more sensitive skin which also leads to breakouts, and it can take a bit longer to heal and resolve completely. I loved using the Vitamin C 23 serum, especially in conjunction with the Cosrx Niacinamide 15. The combination together was so effective for my skin! My face was glowing and my skin felt so hydrated and smooth. I have been applying these to my skin at night for the past month and Im truly amazed at the transformation of my skin texture and appearance. I do not use these in my morning routine. I had no sunburn, dryness or congestion issues whilst using these products. Any acne I experience was minimal and resolved quicker than normal. When you first open the bottle, there is a strong smell. It dissipates when applied to the face. After a few uses, i didn't smell it coming from the bottle anymore. I appreciated that a few drops go a long way. I like the bottles and the application syringe, they were easy to use. as I get to the bottom of the bottles it will be interesting to see if there are any issues getting the last drops of product out.

Effective serum!

I received a free bottle of COSRX The Vitamin C 23 serum from Influenster in exchange for my honest review. I honestly wasn’t too sure what to think about this product at first. Because of the high level of vitamin C, it almost smells like canned cat food when you first open it. The consistency also appears like a lightweight oil at first, so I was nervous about it leaving my combination skin oily. All of my concerns were put to rest when I put the product on my face! While it has a strong smell in the bottle, once you put it on your face, you don’t notice a thing. It is light weight and smoothes easily onto skin. The formula absorbs quickly into skin without leaving it looking greasy. After just a few days of using this product I noticed a big improvement in my ... MoreI received a free bottle of COSRX The Vitamin C 23 serum from Influenster in exchange for my honest review. I honestly wasn’t too sure what to think about this product at first. Because of the high level of vitamin C, it almost smells like canned cat food when you first open it. The consistency also appears like a lightweight oil at first, so I was nervous about it leaving my combination skin oily. All of my concerns were put to rest when I put the product on my face! While it has a strong smell in the bottle, once you put it on your face, you don’t notice a thing. It is light weight and smoothes easily onto skin. The formula absorbs quickly into skin without leaving it looking greasy. After just a few days of using this product I noticed a big improvement in my skin tone. I have quite a bit of sun damage from years of living in south Florida by the beach, and this definitely helped reduce some of the discoloration and fine lines. The only thing I did notice is that when I used the product at night, my face felt a little sticky next to my pillow. Other than that, I really enjoyed this product and found it to be very effective! I would recommend this product to both men and women looking to improve the appearance of fine lines and wrinkles, as well as even skin tone.

Great Vitamin C serum!!!

I received this product complementary of influenster and COSRX in exchange for an honest review.This product has a slightly thick, milky texture. It absorbs into the skin quickly and feels nice going on. It has a faint scent that might be sunflower seed oil, one of its ingredients. I’ve used this serum for about 2 weeks now at night time, I apply it after cleansing and toner. It does not dry my skin out much, I just noticed that my skin feels wants a little extra moisture after using it. I follow with a rich moisturizer and it is great. My skin feels smoother and more firm since using this product and I noticed my skin has been a bit less less oily. This serum is great and I love the results I’m seeing so far!Vitamin C SerumContains 23% pure vitamin C and ... MoreI received this product complementary of influenster and COSRX in exchange for an honest review.This product has a slightly thick, milky texture. It absorbs into the skin quickly and feels nice going on. It has a faint scent that might be sunflower seed oil, one of its ingredients. I’ve used this serum for about 2 weeks now at night time, I apply it after cleansing and toner. It does not dry my skin out much, I just noticed that my skin feels wants a little extra moisture after using it. I follow with a rich moisturizer and it is great. My skin feels smoother and more firm since using this product and I noticed my skin has been a bit less less oily. This serum is great and I love the results I’m seeing so far!Vitamin C SerumContains 23% pure vitamin C and propolis that helps to brighten, even the tone and prevents skin oxidation. It has a slight yellow color with a slight viscous consistency. It absorbs quickly on skin and has a natural scent of vitamin C. I remember that it fizzed when I opened its cap, I also experienced a tingling sensation at first application. It means that the ascorbic acid is really active. I only use it at day time and every other day for 3 weeks. It gives a brightening and plump effect on my skin. My dark spots also slightly fades. I always wear sunscreen after using this serum.

Maintained brightness, would recommend for oily/non-sensitive skin. Avoid for sensitive/dry skin

I received this product complimentary from Influenster and COSRX for testing.I've been using COSRX products for over five years and was excited to see the brand launch a Vitamin C product. I used this product for a little over two and a half weeks. I have combination, oily, pale Asian skin. During my use, I noticed the initial stinging on my skin upon each application. I wouldn't say that I have particularly sensitive skin, very few products have broken me out in the past. This serum didn't break me out, but the stinging took some time to get used to, and was particularly bad when I had existing acne on my face. I would warn against this product for sensitive skin types. I am not sure if I received a bad batch, but there was also an intense meaty smell to the serum ... MoreI received this product complimentary from Influenster and COSRX for testing.I've been using COSRX products for over five years and was excited to see the brand launch a Vitamin C product. I used this product for a little over two and a half weeks. I have combination, oily, pale Asian skin. During my use, I noticed the initial stinging on my skin upon each application. I wouldn't say that I have particularly sensitive skin, very few products have broken me out in the past. This serum didn't break me out, but the stinging took some time to get used to, and was particularly bad when I had existing acne on my face. I would warn against this product for sensitive skin types. I am not sure if I received a bad batch, but there was also an intense meaty smell to the serum that I still have not gotten used to. I've tried many Vitamin Cs and none has smelled to this degree. The smell disappears a few minutes after use but makes the user experience unpleasant. The serum also dries down extremely dry which is a pro for my oily skin. and sits well under makeup and other skincare without pilling. I would say that this serum has contributed to keeping my skin tone even throughout the past intense summer, and the aforementioned cons are up to each user. I can see how this serum would fare well with folks with my skin type, versus a bad experience for others with more sensitive, dry skin types.

Must be refrigerated & used within 2 months!

I usually LOVE all COSRX products but was highly disappointed by this Vitamin C serum. First of all, this serum stung and burned my skin everytime I used this. I have been using Vitamin C regularly for over 10 years and never had such a horrible reaction from other similar products. Second, the serum left my very dry, mature skin super sticky. There is no way I can use this product in the morning or under my makeup due to the awful finish. I used this at night with an occlusive moisturizer on top to calm irritation but my face still stuck to my pillow.The other main inconvenience is that the serum oxidizes quickly and must be refrigerated and used within 2 months of opening. This is extremely unfriendly for travel. Had I known this, I would have never bought it. ... MoreI usually LOVE all COSRX products but was highly disappointed by this Vitamin C serum. First of all, this serum stung and burned my skin everytime I used this. I have been using Vitamin C regularly for over 10 years and never had such a horrible reaction from other similar products. Second, the serum left my very dry, mature skin super sticky. There is no way I can use this product in the morning or under my makeup due to the awful finish. I used this at night with an occlusive moisturizer on top to calm irritation but my face still stuck to my pillow.The other main inconvenience is that the serum oxidizes quickly and must be refrigerated and used within 2 months of opening. This is extremely unfriendly for travel. Had I known this, I would have never bought it. The serum started smelling like melted plastic/burnt rubber after 3 weeks of opening, even though I kept the bottle in the refrigerator. I would never purchase this product again.

Nice

This serum contains highly-concentrated, 23% pure vitamin C which helps fade acne scars and hyperpigmentation and brightens the complexion to revitalize dull and dry skin. Its formula is infused with an antioxidant-rich Vitamin E derivative to amplify the effects of Vitamin C and also protects the skin from environmental damage. Sodium hyaluronate in it maintains skin's moisture levels.It also contains allantoin to soothe skin irritation. This serum is also helpful in diminishing fine lines & wrinkles.I like the texture which isn't oily & absorbs fast into the skin. I didn't notice any irritation from it. Although some people are sensitive to Vitamin C so make sure to patch text before using this on the face. And always store this in refrigerator after opening for ... MoreThis serum contains highly-concentrated, 23% pure vitamin C which helps fade acne scars and hyperpigmentation and brightens the complexion to revitalize dull and dry skin. Its formula is infused with an antioxidant-rich Vitamin E derivative to amplify the effects of Vitamin C and also protects the skin from environmental damage. Sodium hyaluronate in it maintains skin's moisture levels.It also contains allantoin to soothe skin irritation. This serum is also helpful in diminishing fine lines & wrinkles.I like the texture which isn't oily & absorbs fast into the skin. I didn't notice any irritation from it. Although some people are sensitive to Vitamin C so make sure to patch text before using this on the face. And always store this in refrigerator after opening for preventing oxidisation. I haven't use this long enough to notice any visible changes but Im sure its gonna work awesome as it looks so promising.

Potent, Effective, But Pungent Smelling

I received this complimentary from CosRx and Influenster in exchange for my honest review.put this liquid Vitamin C in the refrigerator and that helps with oxidation and the smell. The smell isn’t great, and I thought it didn’t bother me at all. I’m used to using the gold standard of Vitamin C and if you know what I’m talking about, you know it smells like hotdog water. It’s the ascorbic acid in it. And the other brand’s smell goes away after you put it on in a very short time. However, CosRx’s Vitamin C smell did NOT dissipate throughout the day. No matter what products I tried to use after application, I realized that the bad smell I was continuing to smell throughout the day, was this product. Anyway, I used this daily in my morning routine bc I use actives and ... MoreI received this complimentary from CosRx and Influenster in exchange for my honest review.put this liquid Vitamin C in the refrigerator and that helps with oxidation and the smell. The smell isn’t great, and I thought it didn’t bother me at all. I’m used to using the gold standard of Vitamin C and if you know what I’m talking about, you know it smells like hotdog water. It’s the ascorbic acid in it. And the other brand’s smell goes away after you put it on in a very short time. However, CosRx’s Vitamin C smell did NOT dissipate throughout the day. No matter what products I tried to use after application, I realized that the bad smell I was continuing to smell throughout the day, was this product. Anyway, I used this daily in my morning routine bc I use actives and prescription retinol at night. It can still be paired with many things like Hyaluronic acid, snail mucin, etc. Vit C is great to pair under sunscreen as it’s been shown in studies to be more effective at neutralizing free radical damage from sun exposure than just sunscreen alone.It’s only been about 2 weeks and I would say I notice my face is possibly slightly brighter, but the thing that I most notice during this short use is that I had zero reaction to it. That’s a big deal for anyone, especially someone who has sensitive skin and rosacea to be able to use 23% pure Vitamin C. Huge!!! It also didn’t decrease my hydration and in fact seems to help maintain it. It claims to help with hyperpigmentation, fading acne scars, diminish fine lines and wrinkles, and plump skin. I can’t speak to those as the only product that would give you that would be a short lived improvement or a machine. This will take a couple more weeks to notice any change in those. The price is AMAZING for the claims and what I’ve seen so far. I still plan on using this and finding ways to hide this smell. If I can’t figure that out, I will absolutely purchase another bottle to see what other benefits I gain from using it. If not, I still may repurchase, but I’m not sure. I do recommend you give it a shot. I’m very sensitive to smell, so this may not bother you at all and the benefits seem to outweigh the bad even if it does.

Quite disappointing

I was gifted the Cosrx C23 serum by Influenster in exchange for my honest review. Unfortunately, this product is far from being the serum of my dreams. It did brighten my skin somewhat, absorbed reasonably well, and caused no irritation - but the experience of using it overall didn't thrill me. Whilst the effects of the product are fine, it doesn't even come close to competing with higher end and luxury brands' formulations that feel delicious to apply and provide undeniably excellent results. What particularly ruins the experience of using this serum, though, is the stench of it. It's unforgivable. I initially thought I may have received a bad bottle, but a quick google search taught me that I'm not alone in being put off by it. It smells strongly like a ... MoreI was gifted the Cosrx C23 serum by Influenster in exchange for my honest review. Unfortunately, this product is far from being the serum of my dreams. It did brighten my skin somewhat, absorbed reasonably well, and caused no irritation - but the experience of using it overall didn't thrill me. Whilst the effects of the product are fine, it doesn't even come close to competing with higher end and luxury brands' formulations that feel delicious to apply and provide undeniably excellent results. What particularly ruins the experience of using this serum, though, is the stench of it. It's unforgivable. I initially thought I may have received a bad bottle, but a quick google search taught me that I'm not alone in being put off by it. It smells strongly like a combination of chicken broth and tuna brine. I'm giving this product two stars because, to a point, it does what it claims to do, but the simple fact is I don't want to put it on my face because of the way it smells, and there's no reason that I can accept for it to smell the way it does.