Compare Products: The Niacinamide 15 Serum vs Vitamin C Suspension 23% + HA Spheres 2%

Who It's Designed For

COSRX
  • Oily and acne-prone skin seeking serious oil control
  • Post-acne marks and hyperpigmentation
  • Enlarged pores and textured skin
  • Users ready to step up from 10% to higher-strength niacinamide
  • Those who prefer minimal-ingredient formulas
The Ordinary
  • Experienced vitamin C users who want maximum potency at minimum cost
  • Those who have built tolerance to lower vitamin C concentrations
  • Users willing to work with a challenging texture for strong active delivery
  • Budget-conscious shoppers seeking L-ascorbic acid at 23%
  • People who use vitamin C as a nighttime treatment

Key Ingredients

COSRX

Niacinamide (15%), Acetyl Glucosamine (2%), Zinc PCA (1%), Allantoin (0.1%)

The Ordinary

23% L-Ascorbic Acid, 2% Sodium Hyaluronate (HA Spheres), Squalane

Product Composition

11% similarity (3 ingredients in common)

Shared Ingredients
butylene glycolethylhexylglycerinsodium phytate
Only in COSRX (13)
waterpentylene glycolniacinamideacetyl glucosamine12-hexanediolzinc pcatrehalosexanthan gumpullulanallantoincitric acidtocopherol
Only in The Ordinary (12)
ascorbic acidsqualaneisodecyl neopentanoateisononyl isononanoatecoconut alkanesethylene/propylene/styrene copolymersilica dimethyl silylateglucomannancoco-caprylate/caprateacrylates/ethylhexyl acrylate crosspolymertrihydroxystearinbht

User Feedback Patterns

COSRX
Oil control standout

Users consistently report significant reduction in daytime oil and shine. Many describe it as the best niacinamide serum they have tried for sebum control.

Lightweight texture praised

Unlike some high-concentration serums, this absorbs quickly without tackiness or residue. Layers well under other products.

Small bottle concern

The 20ml size (vs. 30ml standard) is a common gripe, especially given the price point.

Pore improvement takes time

Users report visible pore improvement around the 3-4 week mark with consistent twice-daily use.

The Ordinary
Intense stinging on first use

Nearly all first-time users report significant stinging and tingling. This subsides for most within 1-2 weeks of regular use as skin builds tolerance.

Pilling is a universal complaint

Layering anything over this product commonly causes pilling. Users have found that applying it as the last step at night or mixing with a drop of oil reduces this issue.

Effective brightening at unbeatable price

Users who tolerate the texture report visible brightening, improved tone, and reduced dark spots. The $8 price point makes it a cult favorite despite the application challenges.

Night-only use recommended by most

Due to texture and pilling issues, most users reserve this for nighttime use. It does not layer well under sunscreen or makeup.

Which Should You Buy?

The Ordinary Vitamin C Suspension 23% + HA Spheres 2% offers great value at a lower price point. COSRX The Niacinamide 15 Serum may be worth the premium if you want Niacinamide (15%).

Premium Pick
Buy COSRX

View Full Product Details

Related Comparisons