For uneven-looking tone or lingering marks, I would put the No.5 serum ahead of the toner on my shortlist: it combines 5% niacinamide with 4% tranexamic acid and 5% panthenol. I would choose the toner when I wanted an essence-style hydration step that also brings niacinamide into the routine. The difference is the focus of the formula, not simply which bottle says “concentrated”.
Numbuzin is a Korean skincare brand organised around numbered lines. No.5 brings together several products marketed for uneven-looking skin tone, including a liquid toner, serum and pads. They share a theme, not one interchangeable formula.
Our Numbuzin numbers guide gives the wider map of the lines, formats and regional names.
The useful surprise is that the toner is not just a watery introduction to the serum. Both feature niacinamide and panthenol. The decision needs a little more thought than “serum means stronger”.
What differs in these two products?
The Olive Young listings linked below lead to a No.5 Glutathione Vitamin Concentrated Toner 200ml Refill Set and a No.5 Glutathione Vitamin Concentrated Serum 30ml Set with six pads. I checked their product-information tables for this comparison.
The toner listing's ingredient sequence matches the brand's Vitamin Boosting Essential Toner reference. Numbuzin describes that toner as essence-like and specifies 50,000ppm niacinamide, equivalent to 5%. The serum's retailer table explicitly lists 5% niacinamide, 5% panthenol and 4% tranexamic acid.
| Detail | No.5 liquid toner | No.5 concentrated serum |
|---|---|---|
| Niacinamide | Brand-stated 5% | Retailer-listed 5% |
| Panthenol | Included; amount not specified in the checked toner list | Retailer-listed 5% |
| Tranexamic acid | Not listed in the checked formula | Retailer-listed 4% |
| Other notable ingredients | Madecassoside, arbutin and several peptides | Alpha-arbutin, shea butter and glutathione |
| Linked pack | 200ml bottle plus 200ml refill | 30ml serum plus six pads |
The serum is therefore a more specific choice if tranexamic acid is the ingredient you want to introduce. It is not automatically a better niacinamide purchase: these references give the same niacinamide percentage.
The useful distinction is what each group is trying to do. Niacinamide is vitamin B3 used for uneven tone and moisture-barrier support; tranexamic acid is used in some cosmetics to improve the appearance of pigmentation, with results depending on the tested formula. Vitamin C is an antioxidant and is also used for uneven tone. Arbutin is another ingredient used for pigmentation-related concerns. Panthenol is a moisturising B5-related ingredient. Glutathione's antioxidant identity does not, on its own, prove that the finished toner brightens skin. Neither a tone-focused ingredient nor the No.5 name promises that a mark will disappear overnight.
The word “vitamin” does not settle it
The checked serum list specifies 2,000ppm 3-O-ethyl ascorbic acid, a vitamin C derivative. It also lists very small amounts of other vitamin C forms. That is a different proposition from a high-percentage pure ascorbic acid serum.
Which step would I add?
If post-blemish marks were the reason for adding a product, the serum would be my more purposeful choice because of its tone-focused combination. I would keep my existing hydrating toner alongside it. If I mainly wanted to replace a watery toner with something essence-like, the No.5 toner would make more sense without adding another serum.
If my routine already included a niacinamide product I liked, I would consider the overlap before adding either. Two bottles carrying the same number do not create two entirely different jobs.
The toner listing allows application with the hands or a cotton pad after cleansing. The serum directions describe spreading an appropriate amount and gently patting it in. The six gift pads are separate products, not evidence that the serum must be used with pads to work. This is a formula comparison, not a wear test or a promise that either product will remove pigmentation.
Product options
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- Numbuzin No.5 Glutathione Vitamin Concentrated Toner 200ml Refill Set at Olive Young Global
- Numbuzin No.5 Glutathione Vitamin Concentrated Serum 30ml Set with six pads at Olive Young Global
My pick for a focused tone-care addition is the serum; my pick for an essence-style toner with niacinamide is the toner. Both offer 5% niacinamide in the checked information. Buying the pair mainly repeats that ingredient, so I would buy the format that answers the actual reason for changing my routine.