Round Lab Birch Juice Moisturizing Sunscreen: What It Is and How to Use It
Product guide · Al Mahara · Updated 1 Nov 2026
Round Lab's Birch Juice Moisturizing Sunscreen is designed to do double duty as a moisturiser, with an SPF50+ PA++++ rating and no white cast, according to the brand.
Here is what it is, who it suits and how to use it. Sources are linked at the end.
What it is
A hydrating daily sunscreen with SPF50+ and PA++++. Round Lab describes a non-sticky, essence-like texture that blends easily and sits well under makeup.
Round Lab also sells a US formula labelled 'UVLock SPF 50'. The version we stock is the SPF50+ PA++++ one described here.
Key ingredients
Round Lab names birch sap (Betula Platyphylla Japonica Juice), niacinamide and hyaluronic acid as the key ingredients, for hydration and a smoother look.
For more on niacinamide, see our niacinamide guide.
Who it suits
Round Lab positions it for all skin types, including sensitive skin. Dry and normal skin tend to like its moisturising finish most.
As with any new product, test it on a small area first if your skin reacts easily.
How to use it
- Apply a generous amount as the last step of your morning skincare.
- Use at least a teaspoon for the face, as the American Academy of Dermatology suggests.
- Reapply every two hours outdoors, and after sweating or swimming.
Where it fits in your routine
On humid days it can replace a separate moisturiser for normal skin. Dry skin can layer it over the matching Birch Juice cream.
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Sources
Product facts are taken from these pages and our product listings. This is a product guide, not a personal review.
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