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COSRX The Vitamin C… vs Kiehl's Retinol Skin… — Which Is Better? | Gracie

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COSRX The Vitamin C 23 Serum vs Kiehl's Retinol Skin-Renewing Daily Micro-Dose Serum

Kiehl's Retinol Skin-Renewing Daily Micro-Dose Serum scores 9.0/9.8 vs COSRX The Vitamin C 23 Serum at 6.7/9.8. Kiehl's Retinol Skin-Renewing Daily Micro-Dose Serum wins for hydration.

Head to head

COSRX

The Vitamin C 23 Serum

serumbudget

6.7

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Niacinamide
Retinol
Hyaluronic Acid
Salicylic Acid

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Kiehl's

Retinol Skin-Renewing Daily Micro-Dose Serum

serumpremium

9.0

Score comparison

Kiehl's Retinol Skin-Renewing Daily Micro-Dose Serum takes this one, winning 3 of 5 attributes.

COSRX wins 0

Tied 2

Kiehl's wins 3

9.0

COSRX

Kiehl's

Ingredient face-off

2% overlap

11COSRX

1Shared

42Kiehl's

Only in COSRX The Vitamin C 23 Serum

10 unique

Ascorbic Acid Water Propanediol Ethyl Ascorbyl Ether Panthenol Sodium Lactate 2-Hexanediol Allantoin Tromethamine Ethyl Hexanediol

Shared ingredients

1 in common

Sodium Hyaluronate

Only in Kiehl's Retinol Skin-Renewing Daily Micro-Dose Serum

41 unique

Aqua/Water Glycerin Butylene Glycol Pentylene Glycol Niacinamide Cetyl Alcohol Isohexadecane Isononyl Isononanoate Diisopropyl Sebacate 2-Oleamido-1+31 more

Why Kiehl's Retinol Skin-Renewing Daily Micro-Dose Serum comes out ahead

Where Kiehl's Retinol Skin-Renewing Daily Micro-Dose Serum really shines is hydration efficacy, scoring 9.6 compared to COSRX The Vitamin C 23 Serum's 3.9. With Glycerin, Butylene Glycol, and Pentylene Glycol in its top ingredients, Kiehl's Retinol Skin-Renewing Daily Micro-Dose Serum delivers stronger moisture-binding capability.

Active Ingredient Strength is another area of separation. Kiehl's Retinol Skin-Renewing Daily Micro-Dose Serum scores 7.8 here versus 4.1 for COSRX The Vitamin C 23 Serum. That difference comes down to how each formula is built — the ingredient list tells the story.

Kiehl's Retinol Skin-Renewing Daily Micro-Dose Serum brings Niacinamide, Acetyl Dipeptide-1 Cetyl Ester, and Adenosine as actives, while cOSRX The Vitamin C 23 Serum relies on Ascorbic Acid and Allantoin. Both approaches have merit, but the positioning and supporting ingredients make the difference.

Best for your skin type

COSRX The Vitamin C 23 Serum is better if you have

Sensitive skin — the low-irritation formula keeps things gentle
Anyone who prefers clean, well-vetted formulations

Kiehl's Retinol Skin-Renewing Daily Micro-Dose Serum is better if you have

Sensitive skin — the low-irritation formula keeps things gentle
Dry or dehydrated skin that craves moisture, thanks to Glycerin
Targeting specific concerns like aging or uneven tone — Niacinamide does the heavy lifting

Value comparison

At budget pricing with a score of 6.7, COSRX The Vitamin C 23 Serum is a decent pick. Kiehl's Retinol Skin-Renewing Daily Micro-Dose Serum sits at the premium level with a 9.0 score — the higher investment pays off in formulation quality.

Our verdict

✶ Our verdict

+2.3 lead

Kiehl's Retinol Skin-Renewing Daily Micro-Dose Serum wins this comparison with a meaningfully stronger ingredient profile and overall score.

6.7COSRX

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9.0Kiehl's

Frequently asked questions

Which is better: COSRX The Vitamin C 23 Serum or Kiehl's Retinol Skin-Renewing Daily Micro-Dose Serum?

Based on ingredient analysis, Kiehl's Retinol Skin-Renewing Daily Micro-Dose Serum scores higher overall. See the full score breakdown above for details on each attribute.

Do COSRX The Vitamin C 23 Serum and Kiehl's Retinol Skin-Renewing Daily Micro-Dose Serum share ingredients?

Yes, they share common ingredients. Check the ingredient face-off section above for a detailed comparison.

What's the main difference between COSRX The Vitamin C 23 Serum and Kiehl's Retinol Skin-Renewing Daily Micro-Dose Serum?

The key differences are in their active ingredients and formulation approach. Check the attribute battle above for a detailed breakdown.

Full analysis: COSRX The Vitamin C 23 Serum→Full analysis: Kiehl's Retinol Skin-Renewing Daily Micro-Dose Serum→

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