I Tried a Viral Korean SPF After Billie Eilish's Aesthetician Recommended It—Spoiler Alert, I'm Obsessed


Ask any dermatologist or aesthetician, and they'll tell you that sunscreen is the most critical step in a skincare routine. Without it, all of the other steps, including expensive serums, toners, and moisturizers, are for naught. That's because the sun's UV rays will accelerate aging, create new skin concerns, and most importantly, increase the potential for serious health issues.
Knowing this, I'm super diligent about applying daily sunscreen, but not just any old sunscreen. I've been a beauty editor for close to 10 years. After trying almost every sunscreen formula under the sun (pun intended), I have a strict set of standards for my daily SPF. First, it must be a sensorial delight to apply. I'm talking about a lightweight feel, smooth texture, and absolutely no pilling (under any circumstances). Second, it must provide adequate, broad-spectrum sun protection. (I always aim for SPF 30 or higher.) Third, it must make my skin look better than it did before. Yep. I won't settle for just okay. And I definitely won't settle for a white cast. I want my sunscreen to make my skin look hydrated, plump, and dewy.
Recently, I tried a new Korean sunscreen that checked off every box and more. The best part? It's expert-approved. Billie Eilish's aesthetician gave it a stamp of approval. Keep scrolling to see which sunscreen I won't shut up about.
Round Lab Birch Juice Moisturizing UV Lock Sunscreen SPF 45
SPF: 45 | Type: Chemical | Size: 1.69 oz | Ingredients: Birch sap, allantoin, purslane
Benefits: Broad-spectrum sun protection, blue light protection, antioxidant protection, hydration, skin-soothing formula
Here's the sunscreen in question—Round Lab Birch Juice Moisturizing UV Lock Sunscreen SPF 45. It's a Korean sunscreen that's been formulated to meet U.S. standards. (It's unfortunate for beauty editors and other skincare lovers, but many of the active ingredients in European and Asian sunscreen formulas haven't been approved for the American market—at least not yet.)
The chemical formula offers broad-spectrum SPF 45 plus blue-light protection, with a combination of avobenzone, homosalate, and octisalate. It's the other key ingredients that really set it apart from other formulas I've tried. First, there's the hero ingredient, birch sap, which is an antioxidant and anti-inflammatory. Second, there's allantoin, which is a skin-soothing ingredient. Third, there's Portulaca oleracea extract, which is an antioxidant-rich ingredient that also goes by purslane. Add in skin-quenching humectants, and you have a next-level sunscreen.
The milky formula is so lightweight I don't feel like I'm wearing any sunscreen at all, and I can apply makeup over top of it with zero issue. (I never experience any pilling, creasing, or smudging.) It melts into the skin, so there's no need for harsh rubbing or blending. The best part? There's absolutely no white or gray cast, just smooth, plump, and protected skin. Can you see why I'm obsessed with it now?
Shop More Editor-Approved K-Beauty Products
I love Korean toner pads. These collagen ones are my current obsession.

Kaitlyn McLintock is a Beauty Editor atBest Knockoff Luxury Clothing . She has 10 years of experience in the editorial industry, having previously written for other industry-leading publications, like Byrdie, InStyle, The Zoe Report, Bustle, and others. She covers all things beauty and wellness-related, but she has a special passion for creating skincare content (whether that's writing about an innovative in-office treatment, researching the benefits of a certain ingredient, or testing Wholesale Replica Bag and greatest at-home skin device). Having lived in Los Angeles, California, and Austin, Texas, she has since relocated back to her home state, Michigan. When she's not writing, researching, or testing beauty products, she's working through an ever-growing book collection or swimming in the Great Lakes.
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