This comparison covers Relief Sun on Beauty of Joseon's Japan site and Fresh Sun Serum on Isntree's global site, not Isntree Watery Sun Gel. Isntree sells several sunscreens, so the brand name alone is not a shopping list.124

How do the formulas compare?

FeatureBeauty of Joseon Relief SunIsntree Fresh Sun Serum
ProtectionSPF50+ PA++++SPF50+ PA++++
TextureCreamy, lightweight moisturizer feelThin, transparent serum texture
FinishDewyMoist, non greasy
Formula highlightsRice extract, niacinamide and fermented extractsHyaluronic acid forms, niacinamide, ectoin and plant extracts
FragranceLabeled fragrance freeNo fragrance or parfum listed in the full ingredients
DirectionsLast morning skincare step; reapply at least every 2 hoursLast skincare step; gently pat until absorbed
Listed price¥3,200 for one pack on the Japan site$20.25 sale price; $22.50 regular price for 50ml
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These prices come from different storefronts and currencies, so they do not give a fair cheaper option. Isntree's global store separately lists Hyaluronic Acid Watery Sun Gel 50ml at $21.96, reduced from $24.40; its formula and application details are not interchangeable with Fresh Sun Serum.4

Which should you choose for sensitive skin?

Relief Sun is the better texture match if you want moisture and a dewy finish. Beauty of Joseon describes it as suitable for sensitive skin. Fresh Sun Serum is the better texture match if you dislike a heavier cream feel, rather than a proven gentler alternative.12

Fragrance can irritate sensitive skin, making fragrance a useful thing to check before buying. If your current sunscreen is comfortable, keeping a familiar routine is a more useful starting point than switching brands for the name alone. For skin that reacts to sunscreens, consider a mineral formula instead of limiting the decision to these two.35

Relief Sun: Rice + Probiotics has been renamed Relief Sun: Rice + Niacinamide, with the formula and size unchanged. The update is to the name, because even sunscreen now has administrative work.1

How should you apply and reapply sunscreen?

  1. 1Apply moisturizer first if needed. Beauty of Joseon advises layering Relief Sun over moisturizer for dry, dehydrated or normal skin; oily skin can skip an additional moisturizer.
  2. 2Apply sunscreen generously as the last morning skincare step. Cover all exposed skin, including the face, neck and ears. Applying too little reduces protection.
  3. 3For an outing long enough to risk burning, apply sunscreen 30 minutes before leaving and again just before going out. This is general sunscreen guidance for either choice.
  4. 4Reapply every 2 hours, and after swimming, sweating, towel drying or rubbing sunscreen off. Use a sunscreen labeled water resistant for swimming or sweating.
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SPF measures protection against UVB radiation, not how comfortable a sunscreen feels. Choose protection against both UVA and UVB, and check the expiry date before use. Sunscreen does not replace shade, protective clothing or sunglasses, and wearing it is not a reason to stay in the sun longer.67

Where this answer comes from

  1. 1Relief Sun Sunscreenjp.beautyofjoseon.com
  2. 2Hyaluronic Acid Fresh Sun Serum 50mlisntree-global.com
  3. 3Facebooknewsroom.clevelandclinic.org
  4. 4Sunscreenisntree-global.com
  5. 57 travel skin care tips from dermatologistsaad.org
  6. 6Sunscreen and sun safetynhs.uk
  7. 7Health informationbedminsterfamilypractice.nhs.uk