A serum's hyaluronic acid percentage is printed on the label. What determines how well it actually works is not.
It's an easy number to reach for when comparing serums, and an easy one to misread. A percentage tells you how much of an ingredient is in a formula. It tells you nothing about its structure, how it's built to behave in skin, or what it's actually designed to do once it's there. Two serums can carry the same percentage and perform very differently.
Does a higher percentage of hyaluronic acid mean better hydration?
Not on its own. Hyaluronic acid's effectiveness comes down to molecular weight, not the number on the front of the bottle. A formula built around a single molecular weight will only ever do one job — sit on the surface, or move deeper into skin. Neither on its own is the full picture of what hydrated, resilient skin needs.
What actually determines how well hyaluronic acid works?
The answer is molecular weight — specifically, a range of them. Skin doesn't contain hyaluronic acid at one uniform size. It holds a spectrum, from smaller molecules that move between cells to larger ones that sit at the surface. A formula that mirrors this — rather than isolating a single molecular weight — is working with skin's own architecture, not around it.
Susanne Kaufmann Hyaluron Serum is built on this principle: a multi-molecular-weight complex spanning roughly 50 to 3,000 kDa. Smaller molecules penetrate deeper into the skin. Larger ones remain at the surface, holding moisture where it's needed most. Together, they address hydration at more than one level, rather than concentrating all of their effect in one place.
How does that translate into results?
Structure shows up in performance. Compared with a classic single-molecular-weight hyaluronic acid, this multi-weight approach penetrates 55–125% more effectively — the range in skin allows it to reach depths a single size cannot.
In our own clinical testing on the finished formula, this translated to a 33% increase in immediate skin hydration. It's also been shown to improve the skin's barrier function, support elasticity, and visibly soften the appearance of fine lines over time.
What does this mean for how a serum feels day to day?
It means hydration that isn't just surface-deep, and isn't fleeting either. Skin feels replenished from within, not simply coated. That's the difference formulation makes — not a number, but the way an ingredient is built to work with skin rather than sit on top of it.
The takeaway
Concentration is one data point among many, and rarely the most useful one. What matters more is what an ingredient is built to do once it's on skin — how it moves, where it settles, and what it delivers as a result. That's where the real difference between formulas lies.
Discover Susanne Kaufmann Hyaluron Serum.
