Introduction: The Two Sunscreens That Converted the World to K-Beauty SPF
Korean sunscreens changed the game by proving that sun protection does not have to feel heavy, greasy, or leave a chalky white cast. And no two products embody this revolution better than the Beauty of Joseon Relief Sun: Rice + Probiotics and the Round Lab Birch Juice Moisturizing Sunscreen. Both offer SPF50+ PA++++ protection, both have become international bestsellers, and both feel nothing like the thick, unpleasant sunscreens most people grew up hating.
But despite their similarities on paper, these two sunscreens take meaningfully different approaches. The Beauty of Joseon formula leans on rice extract and probiotics for a nourishing, slightly luminous finish, while Round Lab harnesses birch sap for deep hydration and a more moisturizing feel. Which one is right for your skin type, climate, and daily routine?
We put both through their paces -- testing under makeup, checking for white cast on multiple skin tones, and evaluating long-term wear -- so you can make the right call for 2026.
Quick Comparison Table
| Feature | Beauty of Joseon Relief Sun | Round Lab Birch Juice Sunscreen |
|---|---|---|
| SPF Rating | SPF50+ PA++++ | SPF50+ PA++++ |
| Size | 50ml | 50ml |
| Key Ingredients | Rice Extract, Probiotics, Grain Extracts | Birch Sap, Hyaluronic Acid, Centella Asiatica |
| Filter Type | Chemical (organic) filters | Chemical (organic) filters |
| Texture | Lightweight, slightly creamy | Moisturizing, emollient cream |
| Finish | Natural, slightly dewy-luminous | Dewy, moisturized glow |
| White Cast | None to minimal | None |
| Best For | Normal, combination, oily skin | Dry, normal, sensitive skin |
Ingredients Breakdown
Beauty of Joseon Relief Sun: Rice + Probiotics
True to its brand identity, Beauty of Joseon infuses traditional Korean ingredients into modern formulations. The rice extract serves double duty as both a skin-brightening agent and a natural source of antioxidants. Rice has been used in Korean and Japanese beauty for centuries, and modern research supports its ability to inhibit melanin production and improve skin luminosity.
The probiotic complex (Lactobacillus ferment) strengthens the skin barrier and supports the microbiome, which is particularly valuable in a product worn all day. Additional grain extracts provide nourishment without heaviness. The UV filters are modern chemical (organic) filters that offer broad-spectrum protection without the white cast associated with mineral sunscreens.
Round Lab Birch Juice Moisturizing Sunscreen
Round Lab's formula centers on birch sap (birch juice), a hydrating ingredient rich in naturally occurring amino acids, minerals, and antioxidants. Birch sap has been used in Nordic and Korean skincare traditions for its ability to deeply moisturize without causing congestion. It is particularly effective for skin that tends to feel tight or dehydrated.
Supporting the birch sap are Hyaluronic Acid for moisture binding, Centella Asiatica for calming and anti-inflammatory benefits, and Panthenol for barrier repair. This combination makes the Round Lab sunscreen feel more like a moisturizing cream with SPF than a traditional sunscreen -- which is both its greatest strength and potential limitation.
Ingredient Verdict
Beauty of Joseon focuses on brightening, microbiome support, and lightweight protection. Round Lab focuses on deep hydration, soothing, and barrier support. Both use effective chemical UV filters for high-level sun protection.
Texture and Application
The Beauty of Joseon Relief Sun has a lightweight, slightly creamy texture that spreads easily and absorbs quickly. It leaves behind a natural finish that sits between matte and dewy -- a subtle luminosity that mimics healthy, well-rested skin. This makes it an excellent primer-like base for makeup, as it smooths the skin without adding excess shine. On oily skin, it controls reasonably well for the first few hours but may need blotting by midday in humid conditions.
The Round Lab Birch Juice Sunscreen has a noticeably richer, more emollient texture. It feels genuinely moisturizing during application, which dry skin types will love but oily skin types may find too heavy. The finish is dewier than the BoJ, providing a glossy, hydrated look that pairs beautifully with minimal or no-makeup looks. Under full makeup, the richer texture can sometimes cause foundation to slip in oily areas if not set with powder.
Neither sunscreen leaves a white cast on any skin tone tested, which is a significant advantage of chemical filter formulations. Both are comfortable enough to wear daily without feeling like you have sunscreen on at all.
Results: Real-World Performance
Beauty of Joseon Relief Sun
Over extended daily use, the rice and probiotic formula shows cumulative brightening effects. Users report more even skin tone and improved luminosity after several weeks of consistent use. The sunscreen functions well as both protection and a light treatment product.
In terms of sun protection performance, it holds up well during normal daily activities (commuting, indoor work with window exposure, short outdoor walks). For extended outdoor activities like beach days or hiking, reapplication every two hours is essential, as with any sunscreen.
Under makeup, this sunscreen performs admirably. Foundation and concealer layer smoothly over it, and it does not cause pilling with most skincare routines. This is a major reason for its popularity -- it integrates seamlessly into a full routine.
Round Lab Birch Juice Sunscreen
The hydration benefits are immediately noticeable and persistent. Dry skin types who normally feel tight by midday report comfortable, moisturized skin throughout the day. Over time, the birch sap and centella combination contributes to calmer, less reactive skin -- particularly valuable for sensitive types who often struggle with sunscreen irritation.
Under makeup, the richer formula works best with lighter coverage (tinted moisturizer, BB cream, cushion compact) rather than full-coverage liquid foundation. Setting with a light powder helps prevent the dewy finish from translating into unwanted shine.
For outdoor activities, it performs on par with the BoJ -- solid protection for everyday wear with standard reapplication protocols.
Price and Value
Both sunscreens come in the same 50ml tube size and sit in a similar price range, making this comparison straightforward. The Beauty of Joseon Relief Sun and the Round Lab Birch Juice Sunscreen both represent outstanding value compared to Western and Japanese sunscreens with similar SPF ratings and cosmetic elegance.
If the Round Lab sunscreen replaces both your moisturizer and SPF step for dry skin, it may actually represent better value despite a similar price point, as you are consolidating two products into one.
Which One Should You Choose?
Choose Beauty of Joseon Relief Sun if:
- You have normal, combination, or oily skin
- You wear makeup regularly and need a sunscreen that works as a primer
- You want a lightweight, barely-there feel
- You are interested in brightening benefits from your SPF
- You live in a humid climate where heavy products feel uncomfortable
Choose Round Lab Birch Juice Sunscreen if:
- You have dry, normal, or sensitive skin
- You want your sunscreen to double as a moisturizer
- You prefer a dewy, glass-skin finish
- Your skin is easily irritated by sunscreen ingredients
- You favor minimal makeup or a no-makeup look
Pros and Cons
Beauty of Joseon Relief Sun: Rice + Probiotics
Pros:
- Lightweight, comfortable wear all day
- Excellent as a makeup base and primer
- Cumulative brightening benefits from rice extract
- Probiotic complex supports skin microbiome
- No white cast on any skin tone
- Natural, skin-like finish
Cons:
- May not provide enough hydration for very dry skin
- Can become shiny on very oily skin by midday
- Contains chemical filters (not suitable for those who strictly prefer mineral)
Round Lab Birch Juice Moisturizing Sunscreen
Pros:
- Genuinely moisturizing -- can replace your daytime cream
- Birch sap and centella soothe sensitive, reactive skin
- Beautiful dewy finish for the glass-skin look
- No white cast
- Comfortable even on dry, tight skin
Cons:
- Too rich for oily skin, especially in summer
- Dewy finish can cause makeup to slip without powder
- May feel heavy for those who prefer lightweight sunscreens
- Contains chemical filters (not mineral-based)
The Verdict
These two sunscreens represent the best of what Korean SPF has to offer, and your choice really comes down to skin type and lifestyle.
The Beauty of Joseon Relief Sun is the more versatile, crowd-pleasing option. Its lightweight texture, makeup-friendly finish, and brightening benefits make it a safe recommendation for most skin types, especially normal to oily. It is the sunscreen you recommend to a friend who says they hate sunscreen.
The Round Lab Birch Juice Sunscreen is the specialist choice for dry and sensitive skin. If your skin drinks up moisture and you want a sunscreen that actively contributes to your hydration goals, nothing in this price range does it better. Its soothing formula is also a standout for reactive, rosacea-prone, or barrier-compromised skin.
Explore our complete Korean sunscreen collection to find the right SPF for every skin type and season.
Frequently Asked Questions
Do these sunscreens need to be reapplied every two hours?
For extended outdoor exposure, yes -- every two hours or after sweating or swimming, as recommended by dermatologists. For indoor days with minimal sun exposure (office work, working from home), a morning application with possible midday touch-up is generally sufficient for most people.
Can I use these sunscreens on my body?
While both are formulated for face use, they work perfectly fine on the body. However, the 50ml tube size makes them impractical for full-body application. For body SPF, a larger-format sunscreen is more economical.
Are these sunscreens reef-safe?
Both use chemical (organic) UV filters rather than the oxybenzone and octinoxate that have been banned in some marine environments. However, the term "reef-safe" has no standardized definition. If reef safety is a priority, check the specific UV filters against your local regulations.
Can I skip moisturizer if I use the Round Lab Birch Juice Sunscreen?
For dry to normal skin, the Round Lab sunscreen is moisturizing enough to replace your daytime moisturizer, simplifying your morning routine to cleanser, toner, essence, and this sunscreen. For very dry skin, you may still want a light moisturizer underneath during winter months.
