Ultra Pure High-Potency 1.5% Hyaluronic Acid Serum
Ultra Pure High-Potency 1.5% Hyaluronic Acid Serum
Product Description
Product overview
A minimalist, fast-absorbing hyaluronic acid serum with only 7 ingredients that instantly boosts hydration by 89% and leaves skin feeling plump, supple, and bouncy. Clinically proven to replenish dry skin with just one week of use.
Instant Hydration Boost
Clinically proven to boost hydration by 89% instantly upon application.
Texture & feel
SENSORYInstant Hydration Boost
Clinically proven to boost hydration by 89% instantly upon application.
Minimalist Formula
Only 7 carefully selected ingredients for maximum efficacy and minimal irritation risk.
Visible Plumping
Expert grading shows plumper skin in just 1 week of consistent use.
Sensitive Skin Friendly
Free from fragrances, colorants, and common irritants. CDA recognized for low irritation potential.
Safety & compatibility
SAFEHyaluronic acid is naturally occurring in the body and considered safe for topical use during pregnancy and breastfeeding. No harmful ingredients present.
Contains no fatty acids, oils, esters, ferments, or polysorbates that feed Malassezia yeast. Safe for those prone to fungal acne.
Comedogenic rating of 0/5. Recognized by the Canadian Dermatologist Association as non-comedogenic.
Safe to layer with retinol, vitamin C, AHAs, BHAs, and niacinamide. Acts as a hydrating buffer between actives.
Ingredient breakdown
INGREDIENTSSodium Hyaluronate 1.5%Proven
The salt form of hyaluronic acid, a powerful humectant naturally found in skin. Known for its exceptional ability to hold up to 1000x its weight in water, delivering intense hydration to the skin's surface.
- Function: Attracts and binds moisture to skin's upper layers
- Benefit: Improves skin plumpness, suppleness, and bounce
- Research: Extensively studied humectant with proven hydrating efficacy
Glycerin ~5%Proven
A classic, time-tested humectant found naturally in skin. Studies show glycerin may be even more effective than hyaluronic acid at hydrating skin due to its small molecular size.
- Function: Draws moisture from environment into skin
- Benefit: Improves skin barrier function and long-lasting hydration
- Research: 2016 study found glycerin more effective than AHAs and HA as a humectant
Citric Acid TracepH Adjuster
A natural alpha hydroxy acid used here primarily to adjust the formula's pH to optimal levels for skin compatibility and ingredient stability.
- Function: pH buffer and formula stabilizer
- Concentration: Too low for exfoliation; purely functional
7 ingredients
Aqua/Water, Glycerin, Sodium Hyaluronate, Phenoxyethanol, Chlorphenesin, Tetrasodium Glutamate Diacetate, Citric Acid
Where it fits in your routine
ROUTINEApply after water-based toners, before thicker serums and moisturizers. Can be layered with other Kiehl's Ultra Pure serums.
How to use
HOW TO USECleanse & Prep
Start with clean, slightly damp skin. The serum works best when applied to moist skin to maximize hydration.
Dispense & Apply
Apply 2-3 drops to fingertips and gently press onto face, including around the eye area (avoiding direct contact with eyes).
Pat & Absorb
Gently pat until fully absorbed. The lightweight formula absorbs quickly without sticky residue.
Seal & Protect
Follow with a moisturizer to lock in hydration. In the AM, always finish with SPF sunscreen.
Who is it for?
WHOPerfect for you if:
- You have dry, dehydrated, or dull skin
- You want a simple, no-fuss hydrating serum
- You have sensitive skin that reacts to complex formulas
- You're pregnant or breastfeeding and need safe options
- You suffer from fungal acne and need FA-safe hydration
- You want to add a drop to foundation for a dewy finish
Consider alternatives if:
- You need anti-aging benefits beyond hydration
- You prefer multi-weight hyaluronic acid formulas
- You want additional actives like vitamin C or peptides
- You live in very dry climates (may need occlusive on top)
- You're looking for the most budget-friendly option
Skin type compatibility
SKIN TYPESSpecifically formulated for dry skin. Delivers intense hydration and helps skin retain moisture throughout the day.
Lightweight, oil-free formula absorbs quickly. Provides hydration without adding shine or greasiness.
Balances hydration across all face zones without clogging pores or causing excess oil.
Fragrance-free, minimal ingredient list with low irritation potential. CDA recognized for sensitive skin.
Non-comedogenic (0/5 rating), fungal acne safe. Won't clog pores or trigger breakouts.
Results timeline
ONGOING USEInstant Hydration Boost
Skin feels immediately hydrated and refreshed upon application. Clinical studies show an 89% boost in hydration instantly.
89% hydration boostVisible Plumping & Replenishment
Skin begins to look visibly plumper and more replenished. Dry patches appear smoother and more supple.
83% agree skin looks replenishedImproved Skin Texture
Continued improvement in skin hydration levels. Fine dehydration lines appear reduced and skin feels bouncy.
Sustained hydration improvementLong-Term Hydration Support
With consistent use, skin maintains optimal hydration levels and improved resilience against environmental stressors.
Cumulative benefitsRatings by platform
850+ REVIEWSPros & cons
BALANCEDPraised
- Ultra-minimal 7-ingredient formula reduces irritation risk
- Fast-absorbing, non-sticky texture
- Fragrance-free and colorant-free
- Safe for sensitive, acne-prone, and fungal acne skin
- Pregnancy and breastfeeding safe
- Visibly plumps and hydrates from day one
- Layers well under makeup and other products
- Made in USA with heritage brand quality
Criticized
- Higher price point than drugstore alternatives
- Only one molecular weight of HA (competitors offer multi-weight)
- Small 30ml bottle size
- May need occlusive moisturizer in very dry climates
- No additional actives beyond hydration
- Similar products available at lower prices
Budget-friendly alternatives (dupes)
DUPESHigher HA concentration (2%) with added Vitamin B5 and multiple molecular weights. Slightly stickier texture but excellent hydration at a fraction of the price.
Contains Vichy volcanic water and hyaluronic acid. Slightly more complex formula with added minerals. Great for sensitive skin, similar hydrating results.
Two types of HA plus madecassoside and B5. More complex formula with anti-aging benefits. Contains fragrance, so not as sensitive-skin friendly.
Contains ceramides and vitamin B5 alongside HA. More complex formula with barrier repair benefits. Fragrance-free but not as minimalist.
Comparison with competitors
SIDE-BY-SIDEKiehl's Ultra Pure HA 1.5%
Storage & shelf life
12 MONTHS12 months after opening
Store in a cool, dry place away from direct sunlight. No refrigeration required.
Clear glass bottle with dropper dispenser for precise application
Yes, TSA-approved (30ml is under 100ml/3.4oz carry-on limit)
Frequently asked questions
FAQYes, this serum is considered safe for use during pregnancy and breastfeeding. Hyaluronic acid is a naturally occurring substance in the body and is not absorbed systemically when applied topically. The formula contains no retinoids, salicylic acid, hydroquinone, or other ingredients typically avoided during pregnancy. However, always consult with your healthcare provider if you have specific concerns.
Yes, this serum is fungal acne safe. The formula contains no fatty acids, oils, esters, ferments, or polysorbates that can feed the Malassezia yeast responsible for fungal acne. Its minimal 7-ingredient formula makes it one of the cleanest options for those prone to fungal acne breakouts.
Yes! Hyaluronic acid is compatible with virtually all skincare actives including retinol, vitamin C, AHAs, BHAs, and niacinamide. In fact, it works as an excellent hydrating buffer between potentially irritating actives. Kiehl's recommends layering this serum with their Glycolic Acid or Niacinamide serums for enhanced results.
While this serum is suitable for all skin types, it's particularly beneficial for dry and dehydrated skin. The minimalist formula also makes it excellent for sensitive and reactive skin types. Oily and combination skin types can use it as well, as the lightweight formula absorbs quickly without adding greasiness.
Results begin immediately with an 89% boost in hydration upon application. After 1 week of consistent use, 83% of users in clinical studies agreed their skin looked more replenished, and expert grading confirmed visibly plumper skin. Continued use over 2-4 weeks provides sustained hydration improvement.
Apply this serum after cleansing and toning, but before heavier serums, moisturizers, and oils. The general rule is to apply products from thinnest to thickest consistency. In the morning, follow with moisturizer and SPF. At night, you can layer treatment serums and night cream after this hydrating serum.
No, this serum has a comedogenic rating of 0/5 and is officially recognized by the Canadian Dermatologist Association as non-comedogenic. The ultra-minimal formula contains no pore-clogging ingredients and is safe for acne-prone skin.
The serum has a Period After Opening (PAO) of 12 months. Store it in a cool, dry place away from direct sunlight to maintain efficacy. The 30ml bottle typically lasts 2-3 months with twice-daily use of 2-3 drops per application.
Verdict: Kiehl's Ultra Pure High-Potency 1.5% Hyaluronic Acid Serum is an excellent choice for those seeking a simple, effective hydrating serum with minimal irritation risk. Its 7-ingredient formula is ideal for sensitive skin, fungal acne sufferers, and those who are pregnant or breastfeeding. While pricier than drugstore alternatives like The Ordinary, you're paying for Kiehl's heritage brand quality, clinical testing, and an ultra-pure formulation. Best suited for those who value ingredient transparency and want a hydrating serum they can use without worrying about adverse reactions.
Product Overview
Quick product notes are a great way to check if a product is free from commonly avoided ingredients by skincare enthusiasts. These preferences come about for different reasons depending on the ingredient such as personal experiences, sensitivities, health preferences & etc.
Just because a product is not free from a common preference does not mean it's a bad product! You can make a personal decision whether or not you want to use a product that contains these ingredients or not - click the labels of the preference to read more about them.
Quick Product Notes
Ever used a product that promised a certain effect but provided no results? It might not have contained any notable ingredients that could have been responsible for that promised effect. It doesn't matter what the marketing or packaging «promises» it can do, if it doesn't contain anything that can help - then the likelihood of it helping is low.
We help you identify key notable ingredients that have been shown to help with effects such as acne-fighting, brightening, UV-protection, wound healing & anti-aging to help you achieve your skincare goals smarter. Please note that different notable ingredients have varying levels of research behind them, some are extremely well proven yet some have mixed research in their efficacy.
Just because a product doesn't contain any notable ingredients doesn't mean it's bad. And a product with notable ingredients (or even many) doesn't necessarily guarantee the efficacy of the product performing these effects either. There are other factors such as ingredient quality, concentration and formulation that will ultimately determine this.
Be smart and use this as just a starting point for you to make more informed and smarter choices and compare it with reviews to see if the product is right for you
Notable Effects & Ingredients
Why are some products great for some people and horrible for others? Well everyone has different skin types and different reactions to the same ingredients.
We've identified a range of ingredients that are commonly regarded as potentially good or bad for those with Dry, Oily/Acne-Prone or Sensitive skin.
A product that contains good or bad ingredients for your skin type doesn't always flat out make the entire product good or bad for your skin. There are other factors such as ingredient quality, concentration and formulation that will ultimately determine your skins reaction.
One of the best ways to use this section is to troubleshoot products you've had bad experiences with in the past. Check if it contains any of the marked ingredients to point out suspect ingredients to avoid in the future!
Ingredients Related to Skin Types
Ingredient Safety Breakdown refers to the percentage % of ingredients in different risk categories as classified by EWG (Environment Working Group) if they are available. There are almost endless cosmetic ingredients and they are one of the few organisations globally that have assigned ratings to a lot of the more commonly used ingredients which is why we reference them.
EWG is seen by many to be more on the alarmist side in their assignment of health ratings resulting in rating ingredients as riskier than they actually are. We recommend using this a reference point rather than a strict guide of ingredient safety and to always do further research if into ingredients that you may find suspect.
Ingredient Safety Breakdown
Product ingredient list
| EWG | CIR | Ingredient Name & Cosmetic Functions | Notes |
|---|---|---|---|
| 1 |
Water
Solvent, Skin Conditioning
|
|
|
| 2 |
Glycerin
Solvent, Perfuming, Fragrance, Humectant, Viscosity Decreasing Agent, Hair Conditioning, Skin Protecting, Denaturant, Skin Conditioning
|
Promotes Wound Healing
Hydrating
|
|
| 1 |
Sodium Hyaluronate
Skin Conditioning, Humectant
|
Promotes Wound Healing
Hydrating
|
|
| 4 |
Phenoxyethanol
Fragrance, Preservative
|
|
|
| 0 |
Chlorphenesin
Antimicrobial, Preservative
|
|







