Ultra-Low Molecular Hyaluronic Acid Serum
A lightweight, fast-absorbing vegan serum featuring 14 types of hyaluronic acid with an ultra-low molecular weight of 329 Da for deep penetration. Infused with mineral-rich deep seawater from Ulleung Island, Korea, this fragrance-free formula delivers intense, long-lasting hydration while soothing and strengthening the skin barrier.
✨ Texture & Feel
14-Layer Hyaluronic Acid Complex
Multiple molecular weights (329 Da to 2,000 kDa) penetrate different skin layers for comprehensive hydration from surface to deep dermis.
Ulleung Island Deep Sea Water
Rich in magnesium, calcium, and potassium minerals that help retain moisture, strengthen skin defenses, and prevent dehydration.
Glyceryl Glucoside Technology
Activates aquaporin water channels in skin cells to deliver moisture more efficiently and maintain hydration for up to 24 hours.
Soothing Botanical Complex
Madecassoside, Beta-Glucan, Panthenol, and Allantoin work together to calm irritation, reduce redness, and strengthen the skin barrier.
🛡️ Safety & Compatibility
Free from retinoids, salicylic acid, hydroquinone, and chemical sunscreens. All ingredients are considered safe for use during pregnancy and nursing.
Contains no ferments, fatty acids, esters, or polysorbates that feed malassezia yeast. Verified safe by multiple ingredient checkers.
Lightweight, water-based formula with no pore-clogging oils or heavy emollients. Safe for acne-prone and sensitive skin types.
Clinically tested with a 0.00 hypoallergenic index. Free from artificial fragrances, dyes, parabens, sulfates, and common allergens.
Pairs well with all active ingredients including retinol, vitamin C, AHAs, BHAs, and niacinamide. Use on damp skin for best absorption.
No animal-derived ingredients. Never tested on animals. Isntree is verified cruelty-free by Cruelty-Free Kitty.
🔬 Ingredient Breakdown
💧 14-Type Hyaluronic Acid Complex Multi-Weight Proven
The star of this formula featuring hyaluronic acid at various molecular weights from ultra-low (329 Da) to high (2,000 kDa). Each size serves a different purpose - smaller molecules penetrate deeply while larger ones form a protective moisture barrier on the surface.
- 329 Da Ultra-Low MW: Penetrates deep into the dermis for inner hydration
- 5 kDa Low MW: Provides dense, deep-layer moisture
- 80 kDa Low MW: Delivers targeted deep hydration
- 500 kDa Medium MW: Balances surface and inner skin moisture
- 2,000 kDa High MW: Forms protective moisture barrier on skin surface
🌊 Ulleung Island Deep Sea Water Primary Base Proven
Mineral-rich deep seawater sourced from Ulleung Island, South Korea. Contains naturally occurring magnesium, calcium, and potassium that help maintain skin's moisture balance and support the skin barrier.
- Magnesium: Helps combat acne and skin infections
- Calcium: Supports skin barrier repair and cell renewal
- Potassium: Maintains skin hydration and elasticity
🔬 Glyceryl Glucoside 0.15-0.60% Proven
A sugar-based moisturizing compound that activates aquaporin water channels in skin cells, enhancing the skin's natural ability to transport and retain moisture at the cellular level.
- Research: Stimulates aquaporin-3 expression for improved water transport
- Benefit: Long-lasting hydration that works from within the cells
🌿 Madecassoside Proven
One of the four active compounds from Centella Asiatica (Cica), known for its powerful soothing, wound-healing, and antioxidant properties. Helps calm irritated skin and supports barrier repair.
- Anti-inflammatory: Reduces redness and irritation
- Wound healing: Promotes skin repair and recovery
- Antioxidant: Protects against environmental stressors
🛡️ Beta-Glucan Proven
A polysaccharide known for its exceptional moisture-binding and barrier-strengthening properties. Helps soothe sensitive skin and protect against environmental damage.
- Hydration: Penetrates deeply to provide lasting moisture
- Barrier support: Strengthens the skin's protective function
- Soothing: Calms reactive and sensitive skin
💚 Panthenol (Pro-Vitamin B5) 0.35-0.75% Proven
A humectant and emollient that attracts moisture to the skin and helps maintain softness. Converts to Vitamin B5 in the skin to support healing and reduce inflammation.
- Moisturizing: Attracts and binds water to the skin
- Healing: Supports wound healing and skin recovery
- Anti-inflammatory: Helps calm irritation and redness
34 ingredients
Sea Water, Water, Methylpropanediol, Glycerin, Butylene Glycol, 1,2-Hexanediol, Betaine, Pentylene Glycol, Carbomer, Caprylyl Glycol, Allantoin, Tromethamine, Ethylhexylglycerin, Xanthan Gum, Panthenol, Malachite Extract, Hydrolyzed Hyaluronic Acid, Disodium EDTA, Glyceryl Acrylate/Acrylic Acid Copolymer, Glyceryl Glucoside, Sodium Hyaluronate, Potassium Hyaluronate, Hyaluronic Acid, Hydrolyzed Sodium Hyaluronate, Sodium Acetylated Hyaluronate, Hydroxypropyltrimonium Hyaluronate, Sodium Hyaluronate Crosspolymer, Dimethylsilanol Hyaluronate, Hydrolyzed Calcium Hyaluronate, Sodium Sulfated Hyaluronate, Madecassoside, Beta-Glucan, Sodium Stearoyl Hyaluronate, Sodium Oleoyl Hyaluronate
🔄 Where It Fits in Your Routine
Apply to slightly damp skin after toner for maximum absorption. Can be layered 2-3 times for extra hydration. Best used both AM and PM.
📝 How to Use
Cleanse & Tone
Start with clean skin. Apply your toner and leave skin slightly damp - this helps hyaluronic acid work more effectively by giving it moisture to bind to.
Dispense 2-3 Drops
Using the dropper, place 2-3 drops of serum onto your palm or directly onto different areas of your face. A little goes a long way with this concentrated formula.
Gently Pat to Absorb
Press the serum into your skin using gentle patting motions. Avoid rubbing. The lightweight formula absorbs in approximately 3 seconds.
Layer if Needed
For extra hydration on dry days, apply 1-2 additional layers after the first has absorbed. Follow with your regular moisturizer to seal in hydration.
👤 Who Is It For?
✅ Perfect for you if:
- You have dehydrated skin that needs a moisture boost
- You want lightweight hydration without stickiness or greasiness
- You have oily or combination skin that gets clogged by heavy products
- You need a fungal acne-safe hydrating serum
- You're pregnant or breastfeeding and need safe skincare
- You have sensitive skin that reacts to fragrances
- You want to layer hydration without pilling
- You live in a dry climate or air-conditioned environment
❌ Consider alternatives if:
- You have very dry skin that needs richer, occlusive formulas
- You prefer thick, creamy serum textures
- You want anti-aging actives like retinol or vitamin C in one product
- You live in an extremely humid climate (may feel redundant)
- You prefer scented skincare products
🎯 Skin Type Compatibility
Lightweight, watery texture absorbs instantly without adding shine or greasiness. Perfect for oily skin that still needs hydration.
Provides excellent hydration but may need a heavier moisturizer or facial oil on top to lock in moisture, especially in dry climates.
Ideal for combo skin - hydrates dry areas without overwhelming oily zones. Layers beautifully across different face regions.
Fragrance-free, clinically tested hypoallergenic formula with soothing ingredients. Excellent for reactive, easily irritated skin.
Non-comedogenic rating of 0/5 and fungal acne-safe formula. Won't clog pores or trigger breakouts. Safe for acne-prone skin.
Multiple HA weights help plump fine lines and improve skin texture. Pair with anti-aging actives for comprehensive care.
📈 Results Timeline
Instant Hydration Boost
Skin feels immediately hydrated, plump, and refreshed. The lightweight texture absorbs in seconds without any sticky residue.
95% noticed instant hydrationImproved Skin Texture
Skin begins to feel consistently softer and smoother. Dry patches start to diminish. Makeup applies more evenly.
85% reported smoother skinEnhanced Plumpness & Glow
Visible improvement in skin plumpness and radiance. Fine dehydration lines appear reduced. Skin barrier feels stronger.
78% noticed visible plumpingLong-Term Hydration Balance
Skin maintains optimal hydration levels throughout the day. Overall complexion appears healthier and more resilient.
82% saw lasting improvements⭐ Ratings by Platform
⚖️ Pros & Cons
✅ Praised
- Exceptional hydration with 14 types of hyaluronic acid
- Ultra-lightweight, non-sticky texture
- Absorbs incredibly fast (3 seconds)
- Fragrance-free and hypoallergenic
- Fungal acne and pregnancy safe
- Works well under makeup
- Great value for the ingredient quality
- Layers beautifully without pilling
- Soothing for sensitive and irritated skin
- Vegan and cruelty-free formula
❌ Criticized
- May not be hydrating enough for very dry skin alone
- 50ml bottle runs out quickly with daily use
- Dropper can dispense more than needed
- No anti-aging actives (pure hydration focus)
- Watery texture not preferred by some users
- Packaging design varies between batches
💰 Budget-Friendly Alternatives (Dupes)
Similar K-beauty competitor with 5 types of HA and ceramides. Slightly more watery texture, faster absorption. Better for soothing with panthenol focus, while Isntree excels at barrier repair with glyceryl glucoside.
Western drugstore alternative with 5 forms of HA plus Vitamin B5 and ceramides. Thicker, stickier texture. Lower molecular weight variety but excellent value. May pill under makeup.
Most affordable option with 1% sodium hyaluronate and glycerin. Simpler formula with fewer HA types. Good entry-level option but less sophisticated multi-layer hydration approach.
🔄 Comparison with Competitors
Isntree Ultra-Low Molecular HA Serum
$18.00Torriden Dive-In Serum
$19.00The Ordinary HA 2% + B5
$9.90Good Molecules HA Serum
$6.00📦 Storage & Shelf Life
12 months after opening
Store in a cool, dry place away from direct sunlight. Refrigeration optional but can enhance the cooling sensation upon application.
Glass dropper bottle with eco-friendly paper box packaging. Isntree uses green tea leaf-based packaging materials.
Yes, 50ml is under the 100ml TSA limit for carry-on liquids.
❓ Frequently Asked Questions
Yes, this serum is considered safe during pregnancy and breastfeeding. It contains no retinoids, salicylic acid, hydroquinone, chemical sunscreens, or other ingredients commonly flagged during pregnancy. The formula focuses on hydrating and soothing ingredients like hyaluronic acid, glycerin, panthenol, and botanical extracts that are all pregnancy-safe. However, always consult with your healthcare provider if you have specific concerns.
Yes, this serum is fungal acne safe. It has been verified by multiple ingredient checkers including SkinSort and is free from ferments, fatty acids (like oleic acid), esters, polysorbates, and other ingredients that feed malassezia yeast. The formula relies on water-based humectants and hyaluronic acid variants that do not contribute to fungal acne flares.
Yes, absolutely! This hyaluronic acid serum pairs well with all active ingredients. Apply the HA serum first on damp skin to maximize hydration, then follow with your actives. When using retinol, the HA serum helps buffer potential irritation. With vitamin C, apply HA after your vitamin C serum. With AHAs/BHAs, use the HA serum to hydrate and calm skin post-exfoliation. The serum's soothing ingredients (madecassoside, panthenol, beta-glucan) also help minimize irritation from actives.
This serum is excellent for all skin types but particularly excels for oily, combination, sensitive, and acne-prone skin due to its lightweight, non-comedogenic formula. Oily skin users love the fast absorption without greasiness. Those with dry skin can use it but may need to layer it or follow with a richer moisturizer. It's also ideal for dehydrated skin (skin lacking water but not necessarily oil) and for anyone seeking a fragrance-free, sensitive-skin-friendly hydrator.
You'll notice immediate hydration and skin plumping right after the first application. Within 1-2 weeks of consistent use, skin texture improves and feels consistently softer. By weeks 3-4, you should see visible improvements in skin plumpness, reduced fine dehydration lines, and enhanced glow. For long-term barrier strengthening and optimal hydration balance, continue use for 2+ months. Results may vary based on your skin condition and climate.
Apply this serum after cleansing and toning, on slightly damp skin. In the Korean skincare routine order: Cleanser → Toner → THIS SERUM → Essence/Ampoule → Moisturizer → Sunscreen (AM). The key is to apply it while skin is still damp from toner, as hyaluronic acid needs moisture to bind to. You can layer it 2-3 times for extra hydration before moving to the next step.
No, this serum has a comedogenic rating of 0/5 and will not clog pores. The water-based formula contains no oils, silicones, or heavy emollients that could block pores. All forms of hyaluronic acid used are non-comedogenic humectants. The serum is specifically designed to be safe for acne-prone skin and has been verified as fungal acne safe as well.
The serum has a PAO (Period After Opening) of 12 months. Once opened, use within one year for best efficacy and safety. Store in a cool, dry place away from direct sunlight. The 50ml bottle typically lasts 2-3 months with twice-daily use (2-3 drops per application). Look for any changes in color, smell, or texture as signs the product may have expired.
Verdict: The Isntree Ultra-Low Molecular Hyaluronic Acid Serum stands out in the crowded HA serum market with its impressive 14-type hyaluronic acid complex and thoughtful formulation. The ultra-low 329 Da molecular weight ensures deep penetration, while higher molecular weights provide surface hydration – offering comprehensive moisture at every skin layer. The addition of glyceryl glucoside (for activating water channels), madecassoside (for soothing), and beta-glucan (for barrier repair) elevates this beyond a simple hydrator. Perfect for oily, combination, sensitive, and acne-prone skin types seeking lightweight yet effective hydration. While very dry skin types may need additional products on top, this is an excellent choice for anyone wanting a clean, fragrance-free, fungal acne-safe serum that delivers on its hydration promises.
Original: $3.49
-70%$3.49
$1.05Ultra-Low Molecular Hyaluronic Acid Serum
A lightweight, fast-absorbing vegan serum featuring 14 types of hyaluronic acid with an ultra-low molecular weight of 329 Da for deep penetration. Infused with mineral-rich deep seawater from Ulleung Island, Korea, this fragrance-free formula delivers intense, long-lasting hydration while soothing and strengthening the skin barrier.
✨ Texture & Feel
14-Layer Hyaluronic Acid Complex
Multiple molecular weights (329 Da to 2,000 kDa) penetrate different skin layers for comprehensive hydration from surface to deep dermis.
Ulleung Island Deep Sea Water
Rich in magnesium, calcium, and potassium minerals that help retain moisture, strengthen skin defenses, and prevent dehydration.
Glyceryl Glucoside Technology
Activates aquaporin water channels in skin cells to deliver moisture more efficiently and maintain hydration for up to 24 hours.
Soothing Botanical Complex
Madecassoside, Beta-Glucan, Panthenol, and Allantoin work together to calm irritation, reduce redness, and strengthen the skin barrier.
🛡️ Safety & Compatibility
Free from retinoids, salicylic acid, hydroquinone, and chemical sunscreens. All ingredients are considered safe for use during pregnancy and nursing.
Contains no ferments, fatty acids, esters, or polysorbates that feed malassezia yeast. Verified safe by multiple ingredient checkers.
Lightweight, water-based formula with no pore-clogging oils or heavy emollients. Safe for acne-prone and sensitive skin types.
Clinically tested with a 0.00 hypoallergenic index. Free from artificial fragrances, dyes, parabens, sulfates, and common allergens.
Pairs well with all active ingredients including retinol, vitamin C, AHAs, BHAs, and niacinamide. Use on damp skin for best absorption.
No animal-derived ingredients. Never tested on animals. Isntree is verified cruelty-free by Cruelty-Free Kitty.
🔬 Ingredient Breakdown
💧 14-Type Hyaluronic Acid Complex Multi-Weight Proven
The star of this formula featuring hyaluronic acid at various molecular weights from ultra-low (329 Da) to high (2,000 kDa). Each size serves a different purpose - smaller molecules penetrate deeply while larger ones form a protective moisture barrier on the surface.
- 329 Da Ultra-Low MW: Penetrates deep into the dermis for inner hydration
- 5 kDa Low MW: Provides dense, deep-layer moisture
- 80 kDa Low MW: Delivers targeted deep hydration
- 500 kDa Medium MW: Balances surface and inner skin moisture
- 2,000 kDa High MW: Forms protective moisture barrier on skin surface
🌊 Ulleung Island Deep Sea Water Primary Base Proven
Mineral-rich deep seawater sourced from Ulleung Island, South Korea. Contains naturally occurring magnesium, calcium, and potassium that help maintain skin's moisture balance and support the skin barrier.
- Magnesium: Helps combat acne and skin infections
- Calcium: Supports skin barrier repair and cell renewal
- Potassium: Maintains skin hydration and elasticity
🔬 Glyceryl Glucoside 0.15-0.60% Proven
A sugar-based moisturizing compound that activates aquaporin water channels in skin cells, enhancing the skin's natural ability to transport and retain moisture at the cellular level.
- Research: Stimulates aquaporin-3 expression for improved water transport
- Benefit: Long-lasting hydration that works from within the cells
🌿 Madecassoside Proven
One of the four active compounds from Centella Asiatica (Cica), known for its powerful soothing, wound-healing, and antioxidant properties. Helps calm irritated skin and supports barrier repair.
- Anti-inflammatory: Reduces redness and irritation
- Wound healing: Promotes skin repair and recovery
- Antioxidant: Protects against environmental stressors
🛡️ Beta-Glucan Proven
A polysaccharide known for its exceptional moisture-binding and barrier-strengthening properties. Helps soothe sensitive skin and protect against environmental damage.
- Hydration: Penetrates deeply to provide lasting moisture
- Barrier support: Strengthens the skin's protective function
- Soothing: Calms reactive and sensitive skin
💚 Panthenol (Pro-Vitamin B5) 0.35-0.75% Proven
A humectant and emollient that attracts moisture to the skin and helps maintain softness. Converts to Vitamin B5 in the skin to support healing and reduce inflammation.
- Moisturizing: Attracts and binds water to the skin
- Healing: Supports wound healing and skin recovery
- Anti-inflammatory: Helps calm irritation and redness
34 ingredients
Sea Water, Water, Methylpropanediol, Glycerin, Butylene Glycol, 1,2-Hexanediol, Betaine, Pentylene Glycol, Carbomer, Caprylyl Glycol, Allantoin, Tromethamine, Ethylhexylglycerin, Xanthan Gum, Panthenol, Malachite Extract, Hydrolyzed Hyaluronic Acid, Disodium EDTA, Glyceryl Acrylate/Acrylic Acid Copolymer, Glyceryl Glucoside, Sodium Hyaluronate, Potassium Hyaluronate, Hyaluronic Acid, Hydrolyzed Sodium Hyaluronate, Sodium Acetylated Hyaluronate, Hydroxypropyltrimonium Hyaluronate, Sodium Hyaluronate Crosspolymer, Dimethylsilanol Hyaluronate, Hydrolyzed Calcium Hyaluronate, Sodium Sulfated Hyaluronate, Madecassoside, Beta-Glucan, Sodium Stearoyl Hyaluronate, Sodium Oleoyl Hyaluronate
🔄 Where It Fits in Your Routine
Apply to slightly damp skin after toner for maximum absorption. Can be layered 2-3 times for extra hydration. Best used both AM and PM.
📝 How to Use
Cleanse & Tone
Start with clean skin. Apply your toner and leave skin slightly damp - this helps hyaluronic acid work more effectively by giving it moisture to bind to.
Dispense 2-3 Drops
Using the dropper, place 2-3 drops of serum onto your palm or directly onto different areas of your face. A little goes a long way with this concentrated formula.
Gently Pat to Absorb
Press the serum into your skin using gentle patting motions. Avoid rubbing. The lightweight formula absorbs in approximately 3 seconds.
Layer if Needed
For extra hydration on dry days, apply 1-2 additional layers after the first has absorbed. Follow with your regular moisturizer to seal in hydration.
👤 Who Is It For?
✅ Perfect for you if:
- You have dehydrated skin that needs a moisture boost
- You want lightweight hydration without stickiness or greasiness
- You have oily or combination skin that gets clogged by heavy products
- You need a fungal acne-safe hydrating serum
- You're pregnant or breastfeeding and need safe skincare
- You have sensitive skin that reacts to fragrances
- You want to layer hydration without pilling
- You live in a dry climate or air-conditioned environment
❌ Consider alternatives if:
- You have very dry skin that needs richer, occlusive formulas
- You prefer thick, creamy serum textures
- You want anti-aging actives like retinol or vitamin C in one product
- You live in an extremely humid climate (may feel redundant)
- You prefer scented skincare products
🎯 Skin Type Compatibility
Lightweight, watery texture absorbs instantly without adding shine or greasiness. Perfect for oily skin that still needs hydration.
Provides excellent hydration but may need a heavier moisturizer or facial oil on top to lock in moisture, especially in dry climates.
Ideal for combo skin - hydrates dry areas without overwhelming oily zones. Layers beautifully across different face regions.
Fragrance-free, clinically tested hypoallergenic formula with soothing ingredients. Excellent for reactive, easily irritated skin.
Non-comedogenic rating of 0/5 and fungal acne-safe formula. Won't clog pores or trigger breakouts. Safe for acne-prone skin.
Multiple HA weights help plump fine lines and improve skin texture. Pair with anti-aging actives for comprehensive care.
📈 Results Timeline
Instant Hydration Boost
Skin feels immediately hydrated, plump, and refreshed. The lightweight texture absorbs in seconds without any sticky residue.
95% noticed instant hydrationImproved Skin Texture
Skin begins to feel consistently softer and smoother. Dry patches start to diminish. Makeup applies more evenly.
85% reported smoother skinEnhanced Plumpness & Glow
Visible improvement in skin plumpness and radiance. Fine dehydration lines appear reduced. Skin barrier feels stronger.
78% noticed visible plumpingLong-Term Hydration Balance
Skin maintains optimal hydration levels throughout the day. Overall complexion appears healthier and more resilient.
82% saw lasting improvements⭐ Ratings by Platform
⚖️ Pros & Cons
✅ Praised
- Exceptional hydration with 14 types of hyaluronic acid
- Ultra-lightweight, non-sticky texture
- Absorbs incredibly fast (3 seconds)
- Fragrance-free and hypoallergenic
- Fungal acne and pregnancy safe
- Works well under makeup
- Great value for the ingredient quality
- Layers beautifully without pilling
- Soothing for sensitive and irritated skin
- Vegan and cruelty-free formula
❌ Criticized
- May not be hydrating enough for very dry skin alone
- 50ml bottle runs out quickly with daily use
- Dropper can dispense more than needed
- No anti-aging actives (pure hydration focus)
- Watery texture not preferred by some users
- Packaging design varies between batches
💰 Budget-Friendly Alternatives (Dupes)
Similar K-beauty competitor with 5 types of HA and ceramides. Slightly more watery texture, faster absorption. Better for soothing with panthenol focus, while Isntree excels at barrier repair with glyceryl glucoside.
Western drugstore alternative with 5 forms of HA plus Vitamin B5 and ceramides. Thicker, stickier texture. Lower molecular weight variety but excellent value. May pill under makeup.
Most affordable option with 1% sodium hyaluronate and glycerin. Simpler formula with fewer HA types. Good entry-level option but less sophisticated multi-layer hydration approach.
🔄 Comparison with Competitors
Isntree Ultra-Low Molecular HA Serum
$18.00Torriden Dive-In Serum
$19.00The Ordinary HA 2% + B5
$9.90Good Molecules HA Serum
$6.00📦 Storage & Shelf Life
12 months after opening
Store in a cool, dry place away from direct sunlight. Refrigeration optional but can enhance the cooling sensation upon application.
Glass dropper bottle with eco-friendly paper box packaging. Isntree uses green tea leaf-based packaging materials.
Yes, 50ml is under the 100ml TSA limit for carry-on liquids.
❓ Frequently Asked Questions
Yes, this serum is considered safe during pregnancy and breastfeeding. It contains no retinoids, salicylic acid, hydroquinone, chemical sunscreens, or other ingredients commonly flagged during pregnancy. The formula focuses on hydrating and soothing ingredients like hyaluronic acid, glycerin, panthenol, and botanical extracts that are all pregnancy-safe. However, always consult with your healthcare provider if you have specific concerns.
Yes, this serum is fungal acne safe. It has been verified by multiple ingredient checkers including SkinSort and is free from ferments, fatty acids (like oleic acid), esters, polysorbates, and other ingredients that feed malassezia yeast. The formula relies on water-based humectants and hyaluronic acid variants that do not contribute to fungal acne flares.
Yes, absolutely! This hyaluronic acid serum pairs well with all active ingredients. Apply the HA serum first on damp skin to maximize hydration, then follow with your actives. When using retinol, the HA serum helps buffer potential irritation. With vitamin C, apply HA after your vitamin C serum. With AHAs/BHAs, use the HA serum to hydrate and calm skin post-exfoliation. The serum's soothing ingredients (madecassoside, panthenol, beta-glucan) also help minimize irritation from actives.
This serum is excellent for all skin types but particularly excels for oily, combination, sensitive, and acne-prone skin due to its lightweight, non-comedogenic formula. Oily skin users love the fast absorption without greasiness. Those with dry skin can use it but may need to layer it or follow with a richer moisturizer. It's also ideal for dehydrated skin (skin lacking water but not necessarily oil) and for anyone seeking a fragrance-free, sensitive-skin-friendly hydrator.
You'll notice immediate hydration and skin plumping right after the first application. Within 1-2 weeks of consistent use, skin texture improves and feels consistently softer. By weeks 3-4, you should see visible improvements in skin plumpness, reduced fine dehydration lines, and enhanced glow. For long-term barrier strengthening and optimal hydration balance, continue use for 2+ months. Results may vary based on your skin condition and climate.
Apply this serum after cleansing and toning, on slightly damp skin. In the Korean skincare routine order: Cleanser → Toner → THIS SERUM → Essence/Ampoule → Moisturizer → Sunscreen (AM). The key is to apply it while skin is still damp from toner, as hyaluronic acid needs moisture to bind to. You can layer it 2-3 times for extra hydration before moving to the next step.
No, this serum has a comedogenic rating of 0/5 and will not clog pores. The water-based formula contains no oils, silicones, or heavy emollients that could block pores. All forms of hyaluronic acid used are non-comedogenic humectants. The serum is specifically designed to be safe for acne-prone skin and has been verified as fungal acne safe as well.
The serum has a PAO (Period After Opening) of 12 months. Once opened, use within one year for best efficacy and safety. Store in a cool, dry place away from direct sunlight. The 50ml bottle typically lasts 2-3 months with twice-daily use (2-3 drops per application). Look for any changes in color, smell, or texture as signs the product may have expired.
Verdict: The Isntree Ultra-Low Molecular Hyaluronic Acid Serum stands out in the crowded HA serum market with its impressive 14-type hyaluronic acid complex and thoughtful formulation. The ultra-low 329 Da molecular weight ensures deep penetration, while higher molecular weights provide surface hydration – offering comprehensive moisture at every skin layer. The addition of glyceryl glucoside (for activating water channels), madecassoside (for soothing), and beta-glucan (for barrier repair) elevates this beyond a simple hydrator. Perfect for oily, combination, sensitive, and acne-prone skin types seeking lightweight yet effective hydration. While very dry skin types may need additional products on top, this is an excellent choice for anyone wanting a clean, fragrance-free, fungal acne-safe serum that delivers on its hydration promises.
Product Information
Product Information
Shipping & Returns
Shipping & Returns
Description
A lightweight, fast-absorbing vegan serum featuring 14 types of hyaluronic acid with an ultra-low molecular weight of 329 Da for deep penetration. Infused with mineral-rich deep seawater from Ulleung Island, Korea, this fragrance-free formula delivers intense, long-lasting hydration while soothing and strengthening the skin barrier.
✨ Texture & Feel
14-Layer Hyaluronic Acid Complex
Multiple molecular weights (329 Da to 2,000 kDa) penetrate different skin layers for comprehensive hydration from surface to deep dermis.
Ulleung Island Deep Sea Water
Rich in magnesium, calcium, and potassium minerals that help retain moisture, strengthen skin defenses, and prevent dehydration.
Glyceryl Glucoside Technology
Activates aquaporin water channels in skin cells to deliver moisture more efficiently and maintain hydration for up to 24 hours.
Soothing Botanical Complex
Madecassoside, Beta-Glucan, Panthenol, and Allantoin work together to calm irritation, reduce redness, and strengthen the skin barrier.
🛡️ Safety & Compatibility
Free from retinoids, salicylic acid, hydroquinone, and chemical sunscreens. All ingredients are considered safe for use during pregnancy and nursing.
Contains no ferments, fatty acids, esters, or polysorbates that feed malassezia yeast. Verified safe by multiple ingredient checkers.
Lightweight, water-based formula with no pore-clogging oils or heavy emollients. Safe for acne-prone and sensitive skin types.
Clinically tested with a 0.00 hypoallergenic index. Free from artificial fragrances, dyes, parabens, sulfates, and common allergens.
Pairs well with all active ingredients including retinol, vitamin C, AHAs, BHAs, and niacinamide. Use on damp skin for best absorption.
No animal-derived ingredients. Never tested on animals. Isntree is verified cruelty-free by Cruelty-Free Kitty.
🔬 Ingredient Breakdown
💧 14-Type Hyaluronic Acid Complex Multi-Weight Proven
The star of this formula featuring hyaluronic acid at various molecular weights from ultra-low (329 Da) to high (2,000 kDa). Each size serves a different purpose - smaller molecules penetrate deeply while larger ones form a protective moisture barrier on the surface.
- 329 Da Ultra-Low MW: Penetrates deep into the dermis for inner hydration
- 5 kDa Low MW: Provides dense, deep-layer moisture
- 80 kDa Low MW: Delivers targeted deep hydration
- 500 kDa Medium MW: Balances surface and inner skin moisture
- 2,000 kDa High MW: Forms protective moisture barrier on skin surface
🌊 Ulleung Island Deep Sea Water Primary Base Proven
Mineral-rich deep seawater sourced from Ulleung Island, South Korea. Contains naturally occurring magnesium, calcium, and potassium that help maintain skin's moisture balance and support the skin barrier.
- Magnesium: Helps combat acne and skin infections
- Calcium: Supports skin barrier repair and cell renewal
- Potassium: Maintains skin hydration and elasticity
🔬 Glyceryl Glucoside 0.15-0.60% Proven
A sugar-based moisturizing compound that activates aquaporin water channels in skin cells, enhancing the skin's natural ability to transport and retain moisture at the cellular level.
- Research: Stimulates aquaporin-3 expression for improved water transport
- Benefit: Long-lasting hydration that works from within the cells
🌿 Madecassoside Proven
One of the four active compounds from Centella Asiatica (Cica), known for its powerful soothing, wound-healing, and antioxidant properties. Helps calm irritated skin and supports barrier repair.
- Anti-inflammatory: Reduces redness and irritation
- Wound healing: Promotes skin repair and recovery
- Antioxidant: Protects against environmental stressors
🛡️ Beta-Glucan Proven
A polysaccharide known for its exceptional moisture-binding and barrier-strengthening properties. Helps soothe sensitive skin and protect against environmental damage.
- Hydration: Penetrates deeply to provide lasting moisture
- Barrier support: Strengthens the skin's protective function
- Soothing: Calms reactive and sensitive skin
💚 Panthenol (Pro-Vitamin B5) 0.35-0.75% Proven
A humectant and emollient that attracts moisture to the skin and helps maintain softness. Converts to Vitamin B5 in the skin to support healing and reduce inflammation.
- Moisturizing: Attracts and binds water to the skin
- Healing: Supports wound healing and skin recovery
- Anti-inflammatory: Helps calm irritation and redness
34 ingredients
Sea Water, Water, Methylpropanediol, Glycerin, Butylene Glycol, 1,2-Hexanediol, Betaine, Pentylene Glycol, Carbomer, Caprylyl Glycol, Allantoin, Tromethamine, Ethylhexylglycerin, Xanthan Gum, Panthenol, Malachite Extract, Hydrolyzed Hyaluronic Acid, Disodium EDTA, Glyceryl Acrylate/Acrylic Acid Copolymer, Glyceryl Glucoside, Sodium Hyaluronate, Potassium Hyaluronate, Hyaluronic Acid, Hydrolyzed Sodium Hyaluronate, Sodium Acetylated Hyaluronate, Hydroxypropyltrimonium Hyaluronate, Sodium Hyaluronate Crosspolymer, Dimethylsilanol Hyaluronate, Hydrolyzed Calcium Hyaluronate, Sodium Sulfated Hyaluronate, Madecassoside, Beta-Glucan, Sodium Stearoyl Hyaluronate, Sodium Oleoyl Hyaluronate
🔄 Where It Fits in Your Routine
Apply to slightly damp skin after toner for maximum absorption. Can be layered 2-3 times for extra hydration. Best used both AM and PM.
📝 How to Use
Cleanse & Tone
Start with clean skin. Apply your toner and leave skin slightly damp - this helps hyaluronic acid work more effectively by giving it moisture to bind to.
Dispense 2-3 Drops
Using the dropper, place 2-3 drops of serum onto your palm or directly onto different areas of your face. A little goes a long way with this concentrated formula.
Gently Pat to Absorb
Press the serum into your skin using gentle patting motions. Avoid rubbing. The lightweight formula absorbs in approximately 3 seconds.
Layer if Needed
For extra hydration on dry days, apply 1-2 additional layers after the first has absorbed. Follow with your regular moisturizer to seal in hydration.
👤 Who Is It For?
✅ Perfect for you if:
- You have dehydrated skin that needs a moisture boost
- You want lightweight hydration without stickiness or greasiness
- You have oily or combination skin that gets clogged by heavy products
- You need a fungal acne-safe hydrating serum
- You're pregnant or breastfeeding and need safe skincare
- You have sensitive skin that reacts to fragrances
- You want to layer hydration without pilling
- You live in a dry climate or air-conditioned environment
❌ Consider alternatives if:
- You have very dry skin that needs richer, occlusive formulas
- You prefer thick, creamy serum textures
- You want anti-aging actives like retinol or vitamin C in one product
- You live in an extremely humid climate (may feel redundant)
- You prefer scented skincare products
🎯 Skin Type Compatibility
Lightweight, watery texture absorbs instantly without adding shine or greasiness. Perfect for oily skin that still needs hydration.
Provides excellent hydration but may need a heavier moisturizer or facial oil on top to lock in moisture, especially in dry climates.
Ideal for combo skin - hydrates dry areas without overwhelming oily zones. Layers beautifully across different face regions.
Fragrance-free, clinically tested hypoallergenic formula with soothing ingredients. Excellent for reactive, easily irritated skin.
Non-comedogenic rating of 0/5 and fungal acne-safe formula. Won't clog pores or trigger breakouts. Safe for acne-prone skin.
Multiple HA weights help plump fine lines and improve skin texture. Pair with anti-aging actives for comprehensive care.
📈 Results Timeline
Instant Hydration Boost
Skin feels immediately hydrated, plump, and refreshed. The lightweight texture absorbs in seconds without any sticky residue.
95% noticed instant hydrationImproved Skin Texture
Skin begins to feel consistently softer and smoother. Dry patches start to diminish. Makeup applies more evenly.
85% reported smoother skinEnhanced Plumpness & Glow
Visible improvement in skin plumpness and radiance. Fine dehydration lines appear reduced. Skin barrier feels stronger.
78% noticed visible plumpingLong-Term Hydration Balance
Skin maintains optimal hydration levels throughout the day. Overall complexion appears healthier and more resilient.
82% saw lasting improvements⭐ Ratings by Platform
⚖️ Pros & Cons
✅ Praised
- Exceptional hydration with 14 types of hyaluronic acid
- Ultra-lightweight, non-sticky texture
- Absorbs incredibly fast (3 seconds)
- Fragrance-free and hypoallergenic
- Fungal acne and pregnancy safe
- Works well under makeup
- Great value for the ingredient quality
- Layers beautifully without pilling
- Soothing for sensitive and irritated skin
- Vegan and cruelty-free formula
❌ Criticized
- May not be hydrating enough for very dry skin alone
- 50ml bottle runs out quickly with daily use
- Dropper can dispense more than needed
- No anti-aging actives (pure hydration focus)
- Watery texture not preferred by some users
- Packaging design varies between batches
💰 Budget-Friendly Alternatives (Dupes)
Similar K-beauty competitor with 5 types of HA and ceramides. Slightly more watery texture, faster absorption. Better for soothing with panthenol focus, while Isntree excels at barrier repair with glyceryl glucoside.
Western drugstore alternative with 5 forms of HA plus Vitamin B5 and ceramides. Thicker, stickier texture. Lower molecular weight variety but excellent value. May pill under makeup.
Most affordable option with 1% sodium hyaluronate and glycerin. Simpler formula with fewer HA types. Good entry-level option but less sophisticated multi-layer hydration approach.
🔄 Comparison with Competitors
Isntree Ultra-Low Molecular HA Serum
$18.00Torriden Dive-In Serum
$19.00The Ordinary HA 2% + B5
$9.90Good Molecules HA Serum
$6.00📦 Storage & Shelf Life
12 months after opening
Store in a cool, dry place away from direct sunlight. Refrigeration optional but can enhance the cooling sensation upon application.
Glass dropper bottle with eco-friendly paper box packaging. Isntree uses green tea leaf-based packaging materials.
Yes, 50ml is under the 100ml TSA limit for carry-on liquids.
❓ Frequently Asked Questions
Yes, this serum is considered safe during pregnancy and breastfeeding. It contains no retinoids, salicylic acid, hydroquinone, chemical sunscreens, or other ingredients commonly flagged during pregnancy. The formula focuses on hydrating and soothing ingredients like hyaluronic acid, glycerin, panthenol, and botanical extracts that are all pregnancy-safe. However, always consult with your healthcare provider if you have specific concerns.
Yes, this serum is fungal acne safe. It has been verified by multiple ingredient checkers including SkinSort and is free from ferments, fatty acids (like oleic acid), esters, polysorbates, and other ingredients that feed malassezia yeast. The formula relies on water-based humectants and hyaluronic acid variants that do not contribute to fungal acne flares.
Yes, absolutely! This hyaluronic acid serum pairs well with all active ingredients. Apply the HA serum first on damp skin to maximize hydration, then follow with your actives. When using retinol, the HA serum helps buffer potential irritation. With vitamin C, apply HA after your vitamin C serum. With AHAs/BHAs, use the HA serum to hydrate and calm skin post-exfoliation. The serum's soothing ingredients (madecassoside, panthenol, beta-glucan) also help minimize irritation from actives.
This serum is excellent for all skin types but particularly excels for oily, combination, sensitive, and acne-prone skin due to its lightweight, non-comedogenic formula. Oily skin users love the fast absorption without greasiness. Those with dry skin can use it but may need to layer it or follow with a richer moisturizer. It's also ideal for dehydrated skin (skin lacking water but not necessarily oil) and for anyone seeking a fragrance-free, sensitive-skin-friendly hydrator.
You'll notice immediate hydration and skin plumping right after the first application. Within 1-2 weeks of consistent use, skin texture improves and feels consistently softer. By weeks 3-4, you should see visible improvements in skin plumpness, reduced fine dehydration lines, and enhanced glow. For long-term barrier strengthening and optimal hydration balance, continue use for 2+ months. Results may vary based on your skin condition and climate.
Apply this serum after cleansing and toning, on slightly damp skin. In the Korean skincare routine order: Cleanser → Toner → THIS SERUM → Essence/Ampoule → Moisturizer → Sunscreen (AM). The key is to apply it while skin is still damp from toner, as hyaluronic acid needs moisture to bind to. You can layer it 2-3 times for extra hydration before moving to the next step.
No, this serum has a comedogenic rating of 0/5 and will not clog pores. The water-based formula contains no oils, silicones, or heavy emollients that could block pores. All forms of hyaluronic acid used are non-comedogenic humectants. The serum is specifically designed to be safe for acne-prone skin and has been verified as fungal acne safe as well.
The serum has a PAO (Period After Opening) of 12 months. Once opened, use within one year for best efficacy and safety. Store in a cool, dry place away from direct sunlight. The 50ml bottle typically lasts 2-3 months with twice-daily use (2-3 drops per application). Look for any changes in color, smell, or texture as signs the product may have expired.
Verdict: The Isntree Ultra-Low Molecular Hyaluronic Acid Serum stands out in the crowded HA serum market with its impressive 14-type hyaluronic acid complex and thoughtful formulation. The ultra-low 329 Da molecular weight ensures deep penetration, while higher molecular weights provide surface hydration – offering comprehensive moisture at every skin layer. The addition of glyceryl glucoside (for activating water channels), madecassoside (for soothing), and beta-glucan (for barrier repair) elevates this beyond a simple hydrator. Perfect for oily, combination, sensitive, and acne-prone skin types seeking lightweight yet effective hydration. While very dry skin types may need additional products on top, this is an excellent choice for anyone wanting a clean, fragrance-free, fungal acne-safe serum that delivers on its hydration promises.
