Description

COSRX The Vitamin C 23 Serum is a concentrated antioxidant serum built around:

Ascorbic Acid – 23%

This is pure Vitamin C, not merely a Vitamin C derivative.

The current official global and Korean Advanced formula places Ascorbic Acid as the second ingredient after water, confirming its unusually high concentration.

The serum also includes:

• 3-O-Ethyl Ascorbic Acid
• Tocotrienols
• Tocopherol
• Glutathione
• Panthenol
• Sodium Hyaluronate
• Adenosine
• Niacinamide
• Squalane
• Allantoin
• Caffeine
• Acetyl Glucosamine
• Licorice Root Extract
• Camellia Japonica Seed Oil
• Beta-Carotene

COSRX refers to its Tocotrienol component as “Super Vitamin E” and combines it with Vitamin C and Glutathione as an antioxidant-support system.

The product uses a water + oil dual-layer style formula, which is why COSRX recommends lightly shaking it after attaching the dropper. This structure also helps provide hydration and supports the stability of the highly concentrated Vitamin C formula.

Key Benefits of COSRX The Vitamin C 23 Serum

• Helps Brighten Dull Skin
  23% pure Ascorbic Acid provides intensive antioxidant and brightening care for tired, uneven-looking skin.
• Targets Dark Spots & Post-Blemish Marks
  COSRX specifically positions the serum for pigmentation, discoloration, and stubborn blemish marks.
• Contains 23% Pure Vitamin C
  The formula contains a verified 23% concentration of Ascorbic Acid rather than relying only on Vitamin C derivatives.
• Supports Smoother-Looking Texture
  Vitamin C, Panthenol, Sodium Hyaluronate, and Allantoin work together to support more refined, hydrated-looking skin.
• Provides Antioxidant Support
  Vitamin C is reinforced by Tocotrienols, Tocopherol, and Glutathione for a broader antioxidant network.
• Helps Improve the Appearance of Early Aging
  COSRX targets elasticity, fine lines, and early signs of aging with Vitamin C plus Adenosine.
• Adds Hydration to a High-Potency Formula
  Sodium Hyaluronate, Panthenol, Squalane, Butylene Glycol, and Allantoin help balance the strong Ascorbic Acid concentration.
• Clinically Tested for Multiple Skin Concerns
  COSRX currently lists non-comedogenic testing, sensitive-skin irritation testing, and primary skin irritation testing for the product.

Key Ingredients & Their Benefits

Current Official Ingredient List

The current global / Advanced formula is:

Aqua/Water, Ascorbic Acid (23%), Butylene Glycol, Dimethicone, Panthenol, 3-O-Ethyl Ascorbic Acid, Squalane, Sodium Hydroxide, Caffeine, Sodium Hyaluronate, Sodium Metaphosphate, Adenosine, Acetyl Glucosamine, Gardenia Florida Fruit Extract, Allantoin, Dextrin, Tocotrienols, Tocopherol, Elaeis Guineensis (Palm) Oil, Arginine, Niacinamide, Pentylene Glycol, Glutathione, Helianthus Annuus (Sunflower) Seed Oil, Methyl Trimethicone, Carthamus Tinctorius (Safflower) Seed Oil, Camellia Japonica Seed Oil, Daucus Carota Sativa (Carrot) Root Extract, Glycyrrhiza Glabra (Licorice) Root Extract, Beta-Carotene.

Always compare this with the physical package sold by Infinity Skincare Solutions because older Korean-market formula records differ slightly from the current Advanced version.

Why Choose COSRX The Vitamin C 23 Serum?

A high-potency Korean serum with 23% pure Vitamin C plus Vitamin E, Glutathione, Hyaluronic Acid, Panthenol, Niacinamide, and Adenosine.

• Verified 23% Pure Ascorbic Acid
  The concentration is clearly stated by COSRX.
• Current High-Strength COSRX Vitamin C Option
  Designed for users who want stronger Vitamin C care than COSRX’s lower-strength 13% formula.
• Includes Tocotrienol + Tocopherol
  Provides additional Vitamin E antioxidant support.
• Contains Glutathione
  Adds complementary antioxidant and brightening support.
• Contains Hyaluronic Acid
  Sodium Hyaluronate helps maintain hydration despite the high active concentration.
• Contains Panthenol & Allantoin
  Adds soothing support to a potentially irritating high-strength Vitamin C formula.
• Contains Niacinamide
  Provides an additional brightening and barrier-support ingredient.
• Clinically Evaluated
  Current official information includes non-comedogenic and irritation testing.
• Korean Functional Cosmetic
  The Korean-market product is registered for both brightening and wrinkle improvement.
• Made in South Korea
  Current records identify AMOREPACIFIC as manufacturer and COSRX as responsible seller.

How to Use

COSRX currently recommends 2–3 drops after cleansing and toning, followed by moisturizer and SPF during daytime use.

COSRX specifically recommends patch testing because the serum contains a high concentration of pure Vitamin C.

Product Specifications

Important Product Name Update

The familiar product is often listed as:

COSRX The Vitamin C 23 Serum 20g

COSRX’s current international site now presents it as:

Advanced The Vitamin C 23 Serum.

The current Advanced version still has:

23% pure Ascorbic Acid

and remains a 20g serum.

If Infinity Skincare Solutions has older packaging that only says The Vitamin C 23 Serum, use the name printed on that physical box while checking the ingredient panel carefully.

Current Formula vs Older Formula

This is particularly important for this product because COSRX has published more than one ingredient version.

Current Advanced Formula

The current official COSRX global and Korean Advanced listings contain:

• Ascorbic Acid 23%
• Butylene Glycol
• Dimethicone
• Panthenol
• 3-O-Ethyl Ascorbic Acid
• Squalane
• Sodium Hydroxide
• Caffeine
• Sodium Hyaluronate
• Sodium Metaphosphate
• Adenosine
• Tocotrienols
• Tocopherol
• Niacinamide
• Glutathione
• botanical oils and extracts.

No Alcohol Denat. appears in this current Advanced INCI.

Older Korean Formula

An older Korean product page lists a somewhat different formula containing:

• Propanediol
• Tromethamine
• Sodium Chloride
• Sodium Sulfite
• Disodium EDTA
• and Alcohol Denat.

Therefore, do not make one universal alcohol-free claim for every old and new bottle.

For current Advanced stock, the current official formula does not list Alcohol Denat.

For older stock, follow the package.

Important 23% Vitamin C Note

The 23% refers specifically to:

Ascorbic Acid

which is the pure form of Vitamin C.

The formula also contains:

3-O-Ethyl Ascorbic Acid

as an additional Vitamin C derivative.

Do not add these together and claim a total Vitamin C concentration above 23%, because COSRX only verifies 23% pure Ascorbic Acid as the headline concentration.

Is This a Beginner Vitamin C Serum?

Not necessarily.

COSRX positions the current 23% formula particularly toward Vitamin C fans who are already familiar with Vitamin C and want a high-potency option.

A beginner or highly reactive user may prefer:

• fewer drops,
• less frequent application,
• or a lower-strength Vitamin C product first.

COSRX separately sells a 13% pure Vitamin C serum, which is positioned as a more everyday-strength option.

Why Must It Be Refrigerated?

Ascorbic Acid is chemically unstable and can oxidize when exposed to:

• heat,
• light,
• air,
• and time.

COSRX therefore instructs users to:

KEEP REFRIGERATED at 3–10°C

and store the bottle upright after opening.

The brand also recommends using the serum within:

2 months after opening.

Refrigeration helps slow deterioration and preserve freshness, but it does not stop oxidation indefinitely.

Is a Slight Yellow Color Normal?

Pure Vitamin C products may naturally show a light yellow tint.

A small amount of yellow coloration does not automatically mean the product is unusable.

However, substantial darkening toward:

• deep yellow,
• orange,
• or brown

can indicate increasing oxidation.

Because COSRX specifically recommends refrigeration and a two-month after-opening period, changes in color, odor, or texture should be monitored closely.

Why Can the Bottle Make a Sound When Opened?

COSRX explicitly notes that gas can develop due to the nature of high-concentration Vitamin C products.

The brand therefore warns:

• do not shake before opening,
• open carefully,
• attach the pipette,
• then shake lightly from side to side.

A sound when opening does not automatically mean the bottle is defective.

COSRX states that the packaging is designed with extra internal space and a specialized cap to manage this behavior.

Can You Use It Every Day?

Yes, if tolerated.

COSRX states that the serum can be used every day, but because of the high pure Vitamin C concentration, irritation is possible.

For first-time use:

• patch test,
• start slowly,
• and reduce frequency if irritation occurs.

A practical introduction may be:

2–3 times per week → every other day → daily if well tolerated.

Can You Use It in the Morning?

Yes.

The serum can be used in either:

AM or PM.

For morning use, follow with sunscreen.

COSRX’s current directions explicitly include moisturizer and SPF after application.

Can You Use It With Retinol?

COSRX currently recommends caution when pairing this high-strength Vitamin C serum with:

• Retinol
• other high-concentration actives
• Copper Peptides.

The brand recommends separating them into different times of day, for example:

Vitamin C – morning

Retinol – evening

rather than layering both strong formulas together.

This reduces the chance of unnecessary irritation.

Can You Use It With Copper Peptides?

COSRX specifically advises against using the Vitamin C 23 Serum in the same routine as high-concentration Copper Peptide products.

Use them at separate times:

Vitamin C in AM / Copper Peptide in PM

or vice versa.

Brand-Reported Clinical Results

COSRX currently publishes results from a 4-week clinical study conducted in Korea in 2025 with 20 adult participants.

The brand reports:

• 34.81% improvement in radiance / brightening
• 92.32% improvement in skin texture
• 30.14% reduction in redness
• 17.43% decrease in pigmentation area
• 15.07% increase in skin elasticity.

These are COSRX-reported clinical results from a small controlled study and should not be interpreted as guarantees that every user will achieve identical changes.

Pros & Cons

COSRX The Vitamin C 23 Serum 20g Price in Bangladesh

The COSRX The Vitamin C 23 Serum 20g price in Bangladesh varies depending on retailer, import source, formula/packaging generation, and promotional discounts.

Current Bangladesh listings checked include approximately ৳1,669 at Rokomari, ৳1,755 at Emart Way Skincare, ৳1,800 at Cosmetics Gallery BD / SkinPlus, and around ৳1,850 at SalonixBD. These are temporary market references and should not be treated as Infinity Skincare Solutions’ permanent selling price.

For the latest COSRX The Vitamin C 23 Serum 20g price in Bangladesh, check Infinity Skincare Solutions or contact customer support.

Why Buy from Infinity Skincare Solutions?

Infinity Skincare Solutions provides 100% authentic international skincare products from carefully selected and trusted brands. We help customers throughout Bangladesh choose products according to their skin type, concern, climate, and everyday skincare routine.

When you shop with Infinity Skincare Solutions, you receive:

• 100% authentic international skincare products
• Trusted Korean skincare shopping in Bangladesh
• Carefully selected global skincare brands
• Fast delivery across Bangladesh
• Cash on delivery availability
• Friendly and responsive customer support
• Product guidance based on your skin type and concern

Choose COSRX The Vitamin C 23 Serum 20g if your main concerns are dark spots, acne marks, dullness, uneven tone, rough texture, or early signs of aging and you are comfortable using a high-strength 23% pure Vitamin C serum with careful refrigeration and sunscreen use.

FAQs

1. How much Vitamin C is in COSRX The Vitamin C 23 Serum?

The current formula contains 23% pure Ascorbic Acid, which is the active pure form of Vitamin C. It also contains 3-O-Ethyl Ascorbic Acid as an additional Vitamin C derivative.

2. Is COSRX Vitamin C 23 good for dark spots and acne marks?

COSRX specifically positions the serum for dark spots, pigmentation, uneven tone, and stubborn blemish marks. Its current clinical data also report improvement in pigmentation area after four weeks.

3. Is COSRX Vitamin C 23 suitable for beginners?

It is a high-strength formula. COSRX currently positions it particularly toward users already familiar with Vitamin C. Beginners and sensitive users should patch test and introduce it gradually.

4. Does COSRX Vitamin C 23 Serum need refrigeration?

Yes. COSRX recommends storing it upright in a refrigerator at 3–10°C after opening to help maintain freshness.

5. How long can I use the serum after opening?

COSRX recommends using the serum within 2 months of opening. Its unopened shelf life is 24 months from manufacture.

6. Can I use COSRX Vitamin C 23 Serum every day?

Yes, if your skin tolerates it. COSRX advises patch testing and reducing frequency if the high Vitamin C concentration causes irritation.

7. Can I use COSRX Vitamin C 23 Serum in the morning?

Yes. Apply approximately 2–3 drops after cleansing and toning, follow with moisturizer, and always use sunscreen during the daytime.

8. Can I use Vitamin C 23 with retinol?

COSRX recommends avoiding simultaneous use with high-strength retinol or other strong actives. Use them at different times of day to reduce irritation risk.

9. Does the current COSRX Vitamin C 23 Serum contain alcohol?

The current Advanced formula does not list Alcohol Denat., but an older Korean formula did contain denatured alcohol. Always check the ingredient list on your exact package.

10. Where can I buy authentic COSRX The Vitamin C 23 Serum 20g in Bangladesh?

You can buy COSRX The Vitamin C 23 Serum 20g from Infinity Skincare Solutions. Check the product page or contact customer support for current price, stock availability, formula version, expiry information, refrigeration guidance, and nationwide delivery.