Actives glossary

Zinc oxide

The one skincare ingredient whose percentage is always on the box, because the law puts it there.

INCI name
Zinc Oxide
Also called
ZnO, mineral filter, physical filter
Family
UV filter
Range seen on labels
10% to 25% in United States sunscreens
Sits well with
niacinamide, ceramides
Needs care with
No common conflict note

Zinc oxide is the broadest single mineral UV filter, covering UVB and most of the UVA range on its own. It is also the reason the sunscreen aisle is the most transparent shelf in skincare.

Why the percentage is always published

In the United States, sunscreen is regulated as an over-the-counter drug. Active ingredients and their percentages appear on a Drug Facts panel by law. Nothing about the skincare industry’s culture produced that transparency, and it is worth noticing how quickly the same brands stop publishing figures the moment a product is a cosmetic instead.

What the percentage does not decide

A higher zinc percentage does not mean a higher SPF. Dispersion, film formation and how much product a person actually applies matter as much as the load. Our sunscreen ranking scores the percentage as a disclosure fact and scores the formulation questions separately.