COSRX The Vitamin C 13 Serum vs Numbuzin No.5 Vitamin Concentrated Serum
Same shelf, different answers — here's the whole picture in one table. Click either product for full ingredient decode, skin-twin reviews and every retailer's landed cost.
COSRX — The Vitamin C 13 SerumFull breakdown →
Numbuzin — No.5 Vitamin Concentrated SerumFull breakdown →
| COSRX The Vitamin C 13 Serum | Numbuzin No.5 Vitamin Concentrated Serum | |
|---|---|---|
| Step | Serum | Serum |
| Price | $21 | $28 |
| Best landed cost | $21 | $26 |
| Rating | ★ 4.4 (1,900) | ★ 4.5 (3,300) |
| Evidence grade | A | B |
| Korea signal | — | #9 serum · Olive Young Korea (seed) |
| Hero ingredients | Vitamin C, Hyaluronic acid, Allantoin | Vitamin C, Niacinamide, Glutathione |
| Best for | Dullness, Dark spots (PIH) | Dullness, Dark spots (PIH) |
| Skin types | Normal, Combination, Dry, Oily, Sensitive | Normal, Combination, Oily, Dry |
| Texture | light | light |
| Tone note | All tones | All tones |
| Fragrance-free | ✓ | ✓ |
| Fungal-acne safe | ✗ | ✗ |
| US stock | ✓ | ✓ |
Our read: COSRX The Vitamin C 13 Serum carries the stronger evidence grade (A); COSRX The Vitamin C 13 Serum wins on landed cost. If your concerns match both, evidence is the tiebreaker we'd use.
Prices and rankings are seed data pending weekly verification. Take the 60-second quiz and both products get a personal match score on their pages.