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Supersize Hyaluronic Acid Serum 100ml Duo
Close-up of a person's eye with text highlighting product benefits
Key claims from recent clinical study of customers using Hyaluronic Acid Serum
How to layer Hyaluronic Acid Serum
Key stats from recent clinical trial of customers trying hyaluronic acid serum
Ingredients in Hyaluronic Acid Serum
Before and after of customer using Hyaluronic Acid Serum
How to use Hyaluronic Acid Serum
Different Hyalurhnic Acid Serum bottle sizes and uses (30ml = 60 uses, 60ml = 120 uses, 100ml = 180 uses)
Model with 100ml Hyaluronic Acid Serum
Model applying Hyaluronic Acid Serum to her face

Supersize Hyaluronic Acid Serum 100ml Duo

Instantly hydrates, plumps & firms skin in a lightweight, non-sticky formula

4.7
Rated 4.7 out of 5 stars
4.7 Stars (2,908 Reviews)
€41,80 (Worth €44,00) / 2 full-size products

What you get: A lightweight hydrating serum that delivers instant and lasting hydration, leaving your skin plump, smooth, and ready for the day. The INKEY cult-favourite hydration serum, clinically proven to deliver instant hydration with 82% of users seeing firmer, smoother skin in just 4 weeks**  

Why it works: 2% Multi-Molecular Hyaluronic Acid holds up to 1000x its weight in water, delivering intense hydration across multiple layers of skin and helps boosts absorption of other products. Matrixyl™ 3000 Peptide helps to pump, firm and smooth skin.

How it feels: Lightweight and hydrating. No greasiness, stickiness, or tackiness. 

When to use: AM & PM. Use this moisturising serum right after your cleanse.   


**4-week independent consumer study of 22 people under dermatological control


This Duo contains x2 Supersize Hyaluronic Acid Serum 100ml

Suitable for:

  • All skin types
  • Sensitive skin
  • Pregnancy & breastfeeding
  • Teen approved

Targets:

  • Fine lines & wrinkles
  • Dehydrated skin
  • Damaged skin barrier

Awards & Features

  • Glamour
  • CEW 2023 award winner
  • get the gloss
  • get the gloss

The cult-favourite, hydration serum that hero that kicked off the The INKEY List obsession

Clinically proven to deliver instant hydration, plump, firm & smooth skin whilst helping to boost the efficacy of every product you layer on top.

  • Hydrates & plumps with immediate results

  • Improve skin firmness by 82% in 4 weeks**

  • Boost absorption of other products in a lightweight, non-sticky formula

Hyaluronic Acid Serum

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  • Before and after showing results of Supersize Hyaluronic Acid Serum 100ml Duo
    "I decided to try Hyaluronic Acid Serum as I'm struggling with acne dry skin from medications. I've been using it for more than a year and my skin is glowing and feels softer than ever! I would definitely recommend this product if you want change your skin for better!"

    Katarzyna

  • Before and after showing results of Supersize Hyaluronic Acid Serum 100ml Duo

    "You have been a part of the past 2 years of my skincare journey. Thank you INKEY!"

    Keanu

  • Before and after showing results of Supersize Hyaluronic Acid Serum 100ml Duo
    "I’ve used INKEY products religiously and my skin is just amazing! This is before I started and what it is like now. My skin's never been better!"

    Adelle

  • Before and after showing results of Supersize Hyaluronic Acid Serum 100ml Duo
    "The INKEY List is the only skincare that's helped my acne-prone skin due to my polycystic ovaries". Lauren has been using Oat Cleansing Balm, Salicylic Acid Cleanser, Hyaluronic Acid Serum, Succinic Acid Treatment and Omega Water Cream since December 2022."

    Lauren

  • Before and after showing results of Supersize Hyaluronic Acid Serum 100ml Duo
    "Just wanted to say I’ve been using your brand for just over a month and the products have really helped with my acne and the scarring! They are amazing and the results are incredible."

    Amy

  • Before and after showing results of Supersize Hyaluronic Acid Serum 100ml Duo
    "I used the online askINKEY service and chose the Hyaluronic Acid Serum, the Succinic Acid Treatment, and the Omega Water Cream. These are my results after 3 months ❤️ "

    Chloe

  • Before and after showing results of Supersize Hyaluronic Acid Serum 100ml Duo
    "Your products have helped me become so much more confident and happy in my skin!"

    Tatiana

4.7
Rated 4.7 out of 5 stars
Based on 2,908 reviews
Reviews Summary
Customers say this serum delivers instant hydration that keeps skin feeling soft and plump throughout the day. The lightweight, non-sticky texture absorbs quickly into skin without leaving residue, making it easy to layer under moisturizers and makeup. Many appreciate its gentle formula and versatile use in both morning and evening routines. Users frequently mention noticing smoother, more hydrated skin with regular use. The larger size offers good value for a daily essential. A few note it works best applied to damp skin, and some experience pilling under makeup.
2,908 reviews
  • margaret w.
    Verified Buyer
    Reviewing
    Hyaluronic Acid Serum - 30ml
    I recommend this product
    Age Range 65+
    Skin Type Normal
    Skin Concerns Dehydration, Fine Lines and Wrinkles, Hyperpigmentation, Under Eye Circles
    Have you purchased an INKEY List product before? Yes
    How long have you used this product for? 3 months +
    Sensitive Skin Suitability Suitable for my sensitive skin
    Rated 5 out of 5 stars
    4 hours ago
    My go to product to reduce dryness

    I use this morning and night as a first coat after cleaning.

    Allways makes my skin feel nourished

  • Henrique S.
    Verified Buyer
    Reviewing
    Supersize Hyaluronic Acid Serum - 100ml
    I recommend this product
    Age Range 45 - 54
    Skin Type Normal
    Skin Concerns Fine Lines and Wrinkles, Puffiness
    Have you purchased an INKEY List product before? Yes
    How long have you used this product for? 3 months +
    Rated 5 out of 5 stars
    Yesterday
    Love it

    It’s simply amazing

  • Gemma R.
    Verified Buyer
    Reviewing
    Hyaluronic Acid Serum - 30ml
    I recommend this product
    Age Range 35 - 44
    Skin Type Normal
    Skin Concerns Breakouts, Texture, Acne Scars, Dull Skin
    Have you purchased an INKEY List product before? Yes
    How long have you used this product for? 3 months +
    Sensitive Skin Suitability I don’t have sensitive skin
    Rated 5 out of 5 stars
    2 days ago
    Love this

    Love this product, been using this for a while and my skin feels so hydrated and smooth. I suffer with breakouts and I can dry my skin out alot with other products to combat them so this serum is perfect for putting back the hydration.