COSRX 23% Ascorbic Acid Pure Vitamin C Serum: Guru Score 66%

What the gurus are saying.

Every take we've logged from this product's reviews across YouTube. Click any row to watch the moment they said it.

All takes Yay takes Nay takes Mixed takes Hide sponsored

~Mixed

"And to me, that means if you can tolerate this product, you're probably going to see enhanced results when it comes to fighting hyperpigmentation because you have all those great brightening ingredients in there in addition to the vitamin C. However, [...] those stronger concentrations can be more irritating for some skin types. So, it is definitely something to look out for. This is sort of a thin, watery serum with a slightly oily texture. I found that it applied quite evenly."

HotandFlashy

1.23M subs

~Yay

"If you're looking for just a straight ascorbic acid based vitamin C serum, the one from COSRX is pretty good. It's 23% that's going to be marked down."

Dr. Vanita Rattan

1.23M subs

~Nay

"This is 23% ascorbic acid pure. This is too high and too irritating for daily use. They put in sodium hyaluronate which is your humectant but there's no other actives in this product. For me this is one to avoid for skin of color. As beautiful as the box is and how strong it is, this is not something that you should be wearing everyday, especially if you've got skin of color or Indian skin and you're in India. This is not the one."

No BS Beauty

89k subs

~Yay

"This one's really nice, it's 12 bucks right now on YesStyle so it's definitely competing with the price of other vitamin C serums. This one's really nice, it uses ascorbic acid as well, but it's very nice and I had this one arrive fresh. I'm not so sure how often COSRX manufactures it though, so keep that little fact in mind because if they manufacture them all at once in one run and you get it five months later, it's not as good."

Cassandra Bankson

2.46M subs

~Yay

"Well there's another option that we got to talk about that rivals some of the clinical stuff. [...] This right here is from COSRX, this is the 23% Ascorbic Acid Pure Vitamin C Serum. Let me tell you, this is like the budget version of Skin Suitical. This is so good as a dupe for the Skin Suitical."

C

CYoung

95k subs

~Yay

"What I don't like about vitamin C in general is that some products are so yellow you look like SpongeBob, and it has a smell that's not easy to apply. This one has a bit of an oil layer so you have to mix it before applying, it does have a scent but I think it's bearable. Overall I love it so much and I think it's worth the hype."

All 2 takes from CYoung

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"What I don't like about vitamin C in general is that some products are so yellow you look like SpongeBob, and it has a smell that's not easy to apply. This one has a bit of an oil layer so you have to mix it before applying, it does have a scent but I think it's bearable. Overall I love it so much and I think it's worth the hype."

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"But if you're used to vitamin C, you can start it from the vitamin 23. Still, that one for the long-term use, I heard many good reviews and I'm still using it. So far, pretty good. So that one better for the vitamin C serum."

AliceintheRabbitHole

59k subs

~Nay

"I didn't love the vitamin C though."

All 4 takes from AliceintheRabbitHole

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"This might be a great product, but [...] I have a bit more of a sensitive skin type, so I did not finish my bottle of this. I don't personally use ascorbic acid because it's a little harsh on me. [...] If you are a bit more tough in your skin you might really like this, it has a great price, 25 dollars, 12.50 in this sale, just make sure you refrigerate it as soon as you open it."

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"I didn't love the vitamin C though."

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"This was gifted to me, and I liked it more than I thought I would. I was a little hesitant up front, it did look a little yellow, but in all fairness it never turned brown on me and it wasn't too irritating. They added a lot of ingredients to help calm and soothe the skin, so even though it's a strong vitamin C serum, my sensitive skin could handle it. That said, I do have a gripe with it."

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"This is the vitamin C 23 and I like it a lot more than I thought I would. When I first got it I wasn't very impressed, it already looked a little yellow out of the packaging. It's a pure ascorbic acid product, and yellow is still okay, it just means it's probably going to turn orange or brown eventually, which is why COSRX recommends storing it in the fridge."

Dr. Jenny Liu

323k subs

~Mixed

"Pure vitamin C anything that is above 20% has been shown to actually not enhance absorption and may actually reduce penetration. The first few uses it definitely burned quite a bit on my skin, it got better with use with daily use, and I attribute that burning to the high concentration of vitamin C which definitely can happen. So if you are someone that is already pretty sensitive to pure vitamin C and have a hard time tolerating it, this may not be a good product for you."

Dr. Aanchal MD

3.49M subs

~Mixed

"This has 23% vitamin C along with vitamin E and hyaluronic acid. It has to be stored in the fridge. It has a slightly dark brown to yellowish color. You just need a few drops to cover the whole face. What I like about this formulation is it is a very potent, effective form of vitamin C. What I didn't like is it is a slightly sticky formulation, so people who have oily skin may not like it."

James Welsh

1.58M subs

~Yay

"I'm falling slowly back in love with vitamin C serum because they don't make them smell like hot dog water anymore and they don't sting. [...] This one has 23 percent pure ascorbic acid, which [...] is a high percentage, but [...] as someone with very easily sensitized skin and rosacea, this doesn't sting, tingle, or burn. They have a hypoallergenic stabilized formula."

What the evidence says.

Independent of what the gurus think, this is what the published research supports about the main active ingredients here.

Vitamin C

Topical vitamin C is an antioxidant with reasonable evidence for dullness and uneven tone. It breaks down in light and air, so how a product is formulated and packaged matters as much as the percentage on the front.

Source: DermNet

Niacinamide

Niacinamide has evidence behind it for redness, uneven tone and supporting the skin barrier, and it is usually well tolerated even by skin that reacts to most things.

Source: DermNet

Humectants and emollients

Ingredients like these draw water into the surface layers and slow how fast it leaves. The evidence is for comfort, softness and hydration rather than for changing the structure of the skin.

Source: DermNet

Frequently asked.

What is COSRX 23% Ascorbic Acid Pure Vitamin C Serum?

A 23% pure ascorbic acid vitamin C serum designed to brighten skin and reduce hyperpigmentation, formulated with vitamin E and hyaluronic acid.

Is COSRX 23% Ascorbic Acid Pure Vitamin C Serum worth it?

The gurus are split. 5 of the 10 gurus give it their stamp of approval while 2 would skip it, which lands it in the middle at a Guru Score of 66%.

What is COSRX 23% Ascorbic Acid Pure Vitamin C Serum's Guru Score?

COSRX 23% Ascorbic Acid Pure Vitamin C Serum holds a Guru Score of 66%. That is our read on how warmly the experts talk about it, based on the verdicts of 10 expert reviewers we have collected.