COSRX - The Vitamin C 13 Serum reviews: 4.7/5 based on 92 analyzed reviews from 2 sites, updated November 2, 2026.
Praised: odeur and prix. Criticized: strong Odor and storage Requirements.
Written by Augur from the 92 reviews analyzed
This serum is highly appreciated for its ability to brighten and even out dull skin, improving overall appearance and smoothing fine lines. Its lightweight, watery texture sinks in quickly, making it a great addition to skincare routines, particularly for oily or sensitive skin, without causing irritation. However, the serum has a distinct, strong odor that some describe as metallic or reminiscent of coffee, though it usually fades quickly. Users should also note that it requires refrigeration to prevent oxidation and maintain its effectiveness.
Really lovely, good for evening dark spots and creating a glow. You have to keep it in the fridge and it does stink. If your skin can tolerate it, I’d definitely go up to 23%. Best to use at night, as it does react with moisturiser (not in a painful way), meaning you can get orange tide marks.
The COSRX Pure Vitamin C 23% Serum has quickly become one of my favorite brightening serums. It’s strong enough to make a visible difference in dullness, uneven skin tone, and fine lines, yet the formula feels balanced thanks to the addition of vitamin E and hyaluronic acid.I noticed my skin looking fresher and more radiant within a few weeks, and with consistent use, my complexion feels smoother and more even. The texture is lightweight, absorbs well, and doesn’t leave a heavy or sticky finish.If you’re looking for a powerful yet hydrating Vitamin C serum, this one really delivers. Just remember, like with all skincare, patience and consistency are key to seeing lasting results.
This is my 4th bottle and the most gentle vitamin C serum I have ever use. Suitable for sensitive skin. Noticeable effect after using second bottle.
Ok
Really lovely, good for evening dark spots and creating a glow. You have to keep it in the fridge and it does stink. If your skin can tolerate it, I’d definitely go up to 23%.…
Nice product.. Looks good on face
The COSRX Pure Vitamin C 23% Serum has quickly become one of my favorite brightening serums. It’s strong enough to make a visible difference in dullness, uneven skin tone, and…
I love the this 😍.
Very good product
This is my 4th bottle and the most gentle vitamin C serum I have ever use. Suitable for sensitive skin. Noticeable effect after using second bottle.
Light weight and absorbs nicely
Lovely product
really loved this! felt like it really started to help with my hyperpigmentation
