COSRX The Vitamin C 23 Serum Versus COSRX The Vitamin C 13 Serum
Updated on June 28, 2024
Overview
What they are
These products are both cruelty-free and reef safe serums. They have a total of 23 ingredients in common
Cool Features
They both contain hyaluronic acid, niacinamide, Vitamin C and Vitamin E
Suited For
They're both likely to be good for fighting acne, anti aging, dry skin, brightening skin, sensitive skin, oily skin, reducing pores, scar healing, dark spots and better texture
Free From
They both do not contain any common allergens, fragrances, parabens or sulfates
What's Inside
They both contain oils
We independently verify ingredients, and our claims are backed by peer-reviewed research. Spot a product that needs an update? Let us know.
Ingredient Info
COSRX The Vitamin C 23 Serum 34 ingredients
COSRX The Vitamin C 13 Serum 25 ingredients
Free from
Safety & Ethics
pH Level 4
Korean Brand
Free from
Safety & Ethics
Korean Brand
At a glance
Click on any of the items below to learn more
COSRX The Vitamin C 23 Serum 34 ingredients
COSRX The Vitamin C 13 Serum 25 ingredients
Ingredients, at a glance
What's in this product, and how it might affect your skin.
Notable Ingredients
Benefits
Concerns
Ingredients, at a glance
What's in this product, and how it might affect your skin.
Notable Ingredients
Benefits
Ingredients Side-by-side
Ingredients Explained
These ingredients are found in both products.
Ingredients higher up in an ingredient list are typically present in a larger amount.
Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.
So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.
You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Stay hydrated!
Learn more about WaterAscorbic Acid is is pure Vitamin C. This form makes up the largest amount of vitamin C found naturally in our skin.
Not only is vitamin C great for your overall health and immune system, it also has plenty of benefits on your skin.
Vitamin C is best used for brightening skin. It improves dark spots, acne scars, and hyperpigmentation. This is because it blocks the process of skin darkening when exposed to UV.
Remember: Vitamin C should not replace sunscreen!
Your skin uses vitamin C to build collagen. Collagen is one key component in having a strong skin barrier and plump skin. Vitamin C also plays a role in regulating collagen, thus making it effective in improving wrinkles and fine lines.
Ascorbic acid shows potent antioxidant activity. As an antioxidant, it helps fight free-radicals. Free-radicals are molecules that may damage your skin cells. These antioxidants also protect skin against UV damage.
The best formulations include Vitamin E and/or ferulic acid. These two ingredients help stabilize and provide a boost in the benefits of ascorbic acid. This is because ascorbic acid becomes unstable when exposed to UV and air. In fact, you can tell your ascorbic acid has oxidized when it turns an orange-yellow color.
Ascorbic acid is generally compatible with other ingredients. However, using ascorbic acid with other active ingredients might cause irritation. Two ingredients: copper ions and benzoyl peroxide, will inactivate ascorbic acid completely.
Read more about other types of Vitamin C:
Foods rich with vitamin C include oranges, strawberries, broccoli, bell peppers, and more. When consuming Vitamin C, your skin receives a portion of the nutrients.
Learn more about Ascorbic AcidTromethamine helps balance the pH and improve the texture of a product. It is synthetically created.
As an emulsifier, Tromethamine prevents oil and water ingredients from separating. This helps stabilize the product and elongate a product's shelf life. Tromethamine also makes a product thicker.
Tromethamine helps balance the pH level of a product. Normal pH level of skin is slightly acidic (~4.75-5.5). The acidity of our skin is maintained by our glands and skin biome. Being slightly acidic allows our skin to create an "acid mantle". This acid mantle is a thin barrier that protects our skin from bacteria and contaminants.
Oral Tromethanmine is an anti-inflammatory drug but plays the role of masking, adding fragrance, and/or balancing pH in skincare.
1,3-Propanediol, 2-amino-2-(hydroxymethyl)-
Learn more about TromethaminePanthenol is a common ingredient that helps hydrate and soothe the skin. It is found naturally in our skin and hair.
There are two forms of panthenol: D and L.
D-panthenol is also known as dexpanthenol. Most cosmetics use dexpanthenol or a mixture of D and L-panthenol.
Panthenol is famous due to its ability to go deeper into the skin's layers. Using this ingredient has numerous pros (and no cons):
Like hyaluronic acid, panthenol is a humectant. Humectants are able to bind and hold large amounts of water to keep skin hydrated.
This ingredient works well for wound healing. It works by increasing tissue in the wound and helps close open wounds.
Once oxidized, panthenol converts to pantothenic acid. Panthothenic acid is found in all living cells.
This ingredient is also referred to as pro-vitamin B5.
Learn more about PanthenolSqualane is an emollient that helps the skin hold onto moisture. It's an oily liquid that occurs naturally in certain types of fish and plant oils.
Because squalane boosts hydration in the skin, it also comes with plenty of benefits: it is an antioxidant and can help fight free radicals and skin damage. Squalane is also found to have a detoxifying effect when applied.
Squalane comes from squalene, which occurs naturally within the sebum of our skin. It is one of the oils our skin produces to keep itself hydrated. Squalane is the hydrogenated version of squalene and has a longer shelf life.
Research shows that squalane is non-irritating (even at 100% concentration).
In general, it's a fantastic ingredient. It does a great job at hydrating the skin, and it's suitable for those with sensitive skin.
The source of squalane may impact malassezia / fungal acne. This is because olive oil derived squalane can contain impurities such as fatty acids and plant waxes. Sugarcane derived squalane is recommended for anyone with malassezia concerns.
Is squalane vegan?
This depends on the source. Squalane can be derived from both plants and animals. Most squalane used in skincare comes from plants.
Please note: the source of squalane is only known if disclosed by the brand. We recommend reaching out to the brand if you have any questions about their squalane.
Read more about squalene with an "e".
Learn more about SqualaneCaffeine is most associated with coffee, tea, and cacao. In skincare, it helps with calming inflammation and anti-aging.
Caffeine is an antioxidants, which help with the signs of aging. This is because antioxidants help fight skin-damaging free radical molecules.
While caffeine is used to treat cellulite and and dark circles, further studies are needed to prove this. It has been believed to help with these skin conditions due to its ability to dilate blood vessels and increase blood flow.
Some studies are looking into caffeine's ability to protect against UV rays.
Learn more about CaffeineSodium Hyaluronate is hyaluronic acid's salt form. It is commonly derived from the sodium salt of hyaluronic acid.
Like hyaluronic acid, it is great at holding water and acts as a humectant. This makes it a great skin hydrating ingredient.
Sodium Hyaluronate is naturally occurring in our bodies and is mostly found in eye fluid and joints.
These are some other common types of Hyaluronic Acid:
Learn more about Sodium HyaluronateSodium Sulfite is a preservative. Preservatives help prevent mold and bacteria from growing in cosmetics.
This ingredient has been shown to break the bonds in hair, acting as a natural straightener.
It is commonly used in food. It should be noted sodium sulfite degrades both vitamins B1 and E.
Fun fact: Sulfites are naturally occuring in wine.
Learn more about Sodium SulfiteDisodium EDTA plays a role in making products more stable by aiding other preservatives.
It is a chelating agent, meaning it neutralizes metal ions that may be found in a product.
Disodium EDTA is a salt of edetic acid and is found to be safe in cosmetic ingredients.
Learn more about Disodium EDTAGlutathione is an antioxidant naturally found in our bodies. It is made up of three amino acids: glycine, cysteine, and glutamic acid.
As an antioxidant, it prevents oxidative damage to parts of our cell.
While glutathione is said to help with fading dark spots, the results from research are inconclusive. Further studies are needed. With that said, gluthatione has been shown to protect our skin from UV-B induced damage.
This ingredient is naturally occurring in plants, animals, fungi, and some bacteria.
Learn more about GlutathioneAdenosine is in every living organism. It is one of four components in nucleic acids that helps store our DNA.
Adenosine has many benefits when used. These benefits include hydrating the skin, smoothing skin, and reducing wrinkles. Once applied, adenosine increases collagen production. It also helps with improving firmness and tissue repair.
Studies have found adenosine may also help with wound healing.
In skincare products, Adenosine is usually derived from yeast.
Learn more about AdenosineAcetyl Glucosamine is an antioxidant and humectant. It is an amino acid sugar and is naturally found in our skin.
The cool thing about this ingredient? It helps the skin produce hyaluronic acid and boost hydration. It also has antioxidant benefits to protect skin cells.
When paired with niacinamide, Acetyl Glucosamine has been shown to be effective at reducing discoloration.
Learn more about Acetyl GlucosamineWe don't have a description for Gardenia Florida Fruit Extract yet.
Allantoin plays a role in soothing and moisturizing the skin. Because of this, it is often added to products with strong active ingredients.
Some studies have shown this ingredient can promote wound healing with higher concentrations.
Allantoin is derived from the comfrey plant but produced synthetically for cosmetic products to ensure purity.
Learn more about AllantoinDextrin is used to thicken a product and helps bind ingredients together. It is created from starch and glycogen.
As an emulsifier, dextrin prevents ingredients from separating. This helps elongate a product's shelf life.
Studies show coating UV filters with dextrin prevents these ingredients from being absorbed. This helps UV ingredients last longer on the skin.
Learn more about DextrinWe don't have a description for Tocotrienols yet.
Tocopherol (also known as Vitamin E) is a common antioxidant used to help protect the skin from free-radicals and strengthen the skin barrier. It's also fat soluble - this means our skin is great at absorbing it.
Vitamin E also helps keep your natural skin lipids healthy. Your lipid skin barrier naturally consists of lipids, ceramides, and fatty acids. Vitamin E offers extra protection for your skin’s lipid barrier, keeping your skin healthy and nourished.
Another benefit is a bit of UV protection. Vitamin E helps reduce the damage caused by UVB rays. (It should not replace your sunscreen). Combining it with Vitamin C can decrease sunburned cells and hyperpigmentation after UV exposure.
You might have noticed Vitamin E + C often paired together. This is because it is great at stabilizing Vitamin C. Using the two together helps increase the effectiveness of both ingredients.
There are often claims that Vitamin E can reduce/prevent scarring, but these claims haven't been confirmed by scientific research.
Learn more about TocopherolElaeis Guineensis Oil comes from the African Palm tree. This tree is native to Western and Southwestern Africa.
This oil is rich in antioxidants such as Vitamin E. Antioxidants may help with anti-aging.
The Vitamin E and fatty acid content give palm oil a skin-hydrating property. Emollients help trap moisture in by creating a film on the skin.
Palm oil is created by either squeezing the fruit or crushing the kernel at the center of the fruit. In the 1800s, archaeologists discovered a 6000 year old Egyptian tomb containing palm oil.
Palm oil is controversial due to its social and environmental impacts. Several organizations are working to make palm oil harvest more sustainable, such as the RSPO.
Learn more about Elaeis Guineensis OilButylene Glycol (or BG) is used within cosmetic products for a few different reasons:
- It is a solvent, meaning that it helps to dissolve other ingredients. This also enhances the absorption of the product into one's skin.
- It is a humectant, which means that it helps attract moisture into the skin.
- It helps improve product application.
Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
Arginine is an amino acid that is important for human development. Your body uses is it to produce hair keratin and skin collagen.
As a cosmetic ingredient, Arginine has antioxidant properties and can also help repair damaged skin. This ingredient is derived either synthetically or from animals.
Arginine isn't fungal acne safe when used in the presence of other lipids (fats, fatty acids, oils, esters, etc). Oils and fats occur naturally within the skin, so take caution when using Arginine if you're prone to fungal acne.
Learn more about ArginineNiacinamide has emerged as an all-star ingredient due to its many benefits.
It is known to treat acne by reducing inflammation. It also helps fade dark-spots and strengthen the skin by promoting the growth of the ceramide barrier.
Other benefits include smoothing wrinkles and minimizing redness.
The cherry on top? Niacinamide can also help build keratin, a protein that keeps skin firm.
When incorporating niacinamide into your routine, look out for concentration amounts. Typically, 5% niacinamide provides benefits such as fading dark spots. However, if you have sensitive skin, it is better to begin with a smaller concentration.
Niacinamide can be mixed with other ingredients to boost benefits. For instance, it has shown to be effective when used with copper, folic acid, and zinc to treat acne.
Learn more about NiacinamidePentylene glycol is typically used within a product to thicken it. It also adds a smooth, soft, and moisturizing feel to the product. It is naturally found in plants such as sugar beets.
The hydrophilic trait of Pentylene Glycol makes it a humectant. As a humectant, Pentylene Glycol helps draw moisture from the air to your skin. This can help keep your skin hydrated.
This property also makes Pentylene Glycol a great texture enhancer. It can also help thicken or stabilize a product.
Pentylene Glycol also acts as a mild preservative and helps to keep a product microbe-free.
Some people may experience mild eye and skin irritation from Pentylene Glycol. We always recommend speaking with a professional about using this ingredient in your routine.
Pentylene Glycol has a low molecular weight and is part of the 1,2-glycol family.
Learn more about Pentylene GlycolGlycyrrhiza Glabra Root Extract is an extract of the roots of Licorice. It has been found to have several benefits such as skin hydrating, conditioning, and soothing.
One component, glabridin, has extra potent antioxidant and soothing properties. It has also been found to block pigmentation from UVB rays in guinea pigs.
Licorice Root also contains a flavonoid. Flavonoids are a natural substance from in plants. Flavonoids also have antioxidant properties.
Another component, glycyrrhizin, has been found to have anti-inflammatory and antimicrobial benefits. This may make licorice root extract effective at treating acne. However, more research is needed to support this.
Liquiritin is one of the flavone compounds found in licorice. It has been found to help lighten skin by preventing tyrosinase from reacting with tyrosine. When the two react, protein is converted to melanin. Melanin is the substance in your body that gives your features pigmentation.
Learn more about Glycyrrhiza Glabra Root ExtractIngredient Ratings
Here's what our community thinks of the ingredients in these products.
When to use
COSRX The Vitamin C 23 Serum 34 ingredients
COSRX The Vitamin C 13 Serum 25 ingredients
Reviews
Here's what our community thinks
COSRX The Vitamin C 23 Serum 34 ingredients
Laila
I didn't like the consistency of this serum at all.
It felt like I was putting oil to my face, but since I always use the whole product to see...
I didn't like the consistency of this serum at all.
It felt like I was putting oil to my face, but since I always use the whole product to see results this did nothing to me other than feeling uncomfortable.
Chien Yun Ang
Cured my acne scars
I had mix feelings when I first bought this as I read that the smell can be off-putting. But I am glad I bought it. My acne...
Cured my acne scars
I had mix feelings when I first bought this as I read that the smell can be off-putting. But I am glad I bought it. My acne scars faded a lot more after 3 days of using it and saw great results in one week. It also didn't break me out despite containing alcohols and oils. It does sting a little on the first application but doesn't irritate my skin. The smell can be quite strong when you first spread it on, but it slowly goes away after awhile.