Molecular Repair Hair Oil
Molecular Repair Hair Oil
Product Description
Product overview
A biotech-engineered, weightless hair oil that fights frizz at two levels of the hair fiber. The patented K18PEPTIDE™ repairs damage from the inside out while natural oils smooth the surface for 24-hour frizz control, 104% more shine, and heat protection up to 450°F (232°C). Silicone-free and suitable for all hair types.
Dual-Level Frizz Repair
K18PEPTIDE™ repairs damage inside the hair cortex while natural oils smooth the cuticle surface for immediate and long-term frizz control.
Texture & feel
SENSORYDual-Level Frizz Repair
K18PEPTIDE™ repairs damage inside the hair cortex while natural oils smooth the cuticle surface for immediate and long-term frizz control.
Heat Protection to 450°F
Avocado oil provides thermal protection up to 232°C (450°F), safeguarding hair during blow-drying, flat-ironing, and curling.
104% Shine Improvement
Clinically proven to boost shine by 104% and reduce split ends by 78% after a single application on dry hair.
Weightless & Silicone-Free
No silicone buildup. Hemisqualane and squalane deliver slip and shine without weighing down even fine hair.
Safety & compatibility
SAFEContains fragrance (parfum) and fragrance allergens (limonene, linalool, cinnamal). No retinoids, salicylic acid, or hydroquinone. Consult your doctor as a precaution due to fragrance components.
Not fungal acne safe. Contains avocado oil (oleic acid-rich) and sunflower oil, which can feed malassezia yeast. Avoid contact with face and scalp if prone to fungal acne.
Rated 1/5 comedogenic. Product is designed for mid-lengths to ends only, not scalp application. Low risk of clogging pores with proper use.
Safe for all color-treated, bleached, and chemically processed hair. Actually enhances color vibrancy and dimension.
No silicones, sulfates, parabens, phthalates, or mineral oils. Clean at Sephora certified. Will not cause product buildup.
Contains cinnamal, hexyl cinnamal, limonene, and linalool — EU-listed fragrance allergens. Patch test if you have sensitive skin or fragrance sensitivities.
Ingredient breakdown
INGREDIENTSK18PEPTIDE™ (sh-Oligopeptide-78) PatentedProven
A bioactive peptide engineered to reconnect broken keratin chains deep within the hair cortex. Unlike traditional bond builders that only target disulfide bonds, K18PEPTIDE™ repairs polypeptide chains as well, addressing a broader spectrum of damage.
- Mechanism: Penetrates the hair fiber to reconnect broken keratin chains at the molecular level
- Clinical Data: 24-hour frizz control in 80% relative humidity; 78% split end reduction
- Advantage: Works across multiple bond types, unlike single-bond repair systems
Avocado Oil (Persea Gratissima) Top 5Proven
A nutrient-rich oil loaded with oleic acid (70%), vitamins A, D, and E. Provides exceptional thermal protection and deep conditioning for the hair shaft.
- Heat Protection: Provides thermal protection up to 450°F (232°C)
- Penetration: Excellent ability to penetrate hair fibers and deliver nourishment to the cortex
- Fatty Acids: Rich in oleic (70%), palmitic (10%), and linoleic acid (8%)
Squalane Top 5Proven
A lightweight, plant-derived emollient that mimics the hair's natural lipid barrier. Delivers deep moisture without greasiness and reinforces the hair's protective moisture barrier.
- Function: Reinforces hair's moisture barrier, smooths flyaways, and enhances shine
- Texture: Extremely lightweight with a non-greasy, silky finish
- Compatibility: Compatible with all hair types; does not cause buildup
Sunflower Oil (Helianthus Annuus) Top 5Proven
Rich in vitamin E and essential fatty acids, sunflower oil coats hair strands to prevent breakage, reduce split ends, and add natural shine.
- Conditioning: Forms a protective barrier that locks in moisture and smooths cuticles
- Vitamins: High in vitamin E (tocopherol) for antioxidant protection
Hemisqualane (C13-15 Alkane) Top 5Promising
A lightweight silicone alternative derived from sugarcane. Provides instant smoothing and detangling without buildup, giving hair a silky, natural feel.
- Silicone Alternative: Delivers slip and shine without silicone-related buildup
- Lightweight: Evaporates partially to leave a dry, non-greasy finish
Tocopherol (Vitamin E) SupportingProven
A powerful antioxidant that protects hair from UV damage and environmental stressors. Helps reduce oxidative stress that leads to dull, brittle hair.
- Antioxidant: Shields hair from free radical damage caused by UV, pollution, and heat
- Conditioning: Supports moisture retention and improves overall hair health
17 ingredients
Caprylyl Caprylate/Caprate, Squalane, Persea Gratissima (Avocado) Oil, Helianthus Annuus (Sunflower) Oil, C13-15 Alkane, Undecane, Benzyl Alcohol, Tridecane, Castor Isostearate Succinate, Propanediol, sh-Oligopeptide-78, Fragrance (Parfum), Tocopherol, Cinnamal, Hexyl Cinnamal, Limonene, Linalool.
Where it fits in your hair routine
ROUTINEUse on damp hair before styling for repair + frizz control. Apply to dry hair as a finishing oil for shine. For maximum repair, use after K18 Leave-In Mask (wait 4 minutes).
How to use
HOW TO USEShampoo & Towel Dry
Wash hair with shampoo. Towel-dry until damp (not dripping wet). Skip conditioner if using the K18 Leave-In Mask beforehand.
Dispense 1-3 Drops
This is a highly concentrated formula. Start with 1 drop for fine hair, 2-3 drops for thick or coily hair. You can always add more.
Apply Mid-Lengths to Ends
Rub between palms and distribute evenly from mid-lengths to ends. Avoid applying directly to the scalp or roots.
Wait 4 Minutes (For Repair Benefits)
For K18PEPTIDE™ strengthening benefits, wait 4 minutes before heat styling. This allows the peptide to penetrate and repair the hair fiber.
Style as Usual or Air Dry
Proceed with blow-drying, flat-ironing, or air-drying. Reapply 1-2 drops on dry hair as a finishing oil to smooth flyaways and boost shine.
Who is it for?
WHOPerfect for you if:
- Your hair is damaged from bleaching, coloring, or heat styling
- You struggle with frizz, especially in humid weather
- You want a silicone-free oil that won't cause buildup
- You need heat protection for blow-drying or flat-ironing
- Your hair looks dull and lacks shine or vibrancy
- You have split ends and breakage from chemical treatments
- You want a lightweight oil that works on fine to thick hair
Consider alternatives if:
- You have fungal acne on your scalp and need scalp contact
- You need deep hydration for extremely dry or coarse hair (pair with a mask)
- You are very sensitive to fragrance or fragrance allergens
- You prefer completely fragrance-free products
- Your budget is tight — this is a premium-priced oil at $65/30ml
Hair type compatibility
SKIN TYPESWeightless formula absorbs without heaviness. Use just 1 drop to avoid weighing hair down. Reviewers with fine hair consistently praise it.
Excellent for smoothing frizz and adding shine. Use 2-3 drops. May need a heavier leave-in for deep hydration on very coarse textures.
Defines curls, reduces frizz in humidity, and boosts shine for 3-5 days. Apply per section for best coverage on coily patterns.
Enhances natural wave pattern, controls flyaways, and adds beautiful shine without disrupting wave definition.
Adds mirror-like shine and smoothness. Use sparingly (1 drop) as straight hair shows product more easily. Great as a blow-dry finisher.
This is where K18 truly excels. Reverses damage from bleach and color services. Enhances color vibrancy and dimension.
Results timeline
2-3 MONTHSInstant Smoothness & Shine
Hair feels silkier, looks shinier (104% improvement clinically proven), and frizz is visibly reduced. Split ends appear sealed. Most dramatic results on damaged or bleached hair.
90% noticed instant shine improvementImproved Manageability & Frizz Control
Hair becomes easier to detangle and style. 24-hour frizz control becomes more consistent, even in humid conditions. Hair feels stronger and more resilient between washes.
80% noticed less breakageVisible Repair & Strength
Cumulative peptide repair builds with each use. Hair shows significantly less breakage, improved elasticity, and enhanced color retention. Split ends reduced by up to 78%.
75% noticed stronger, healthier hairTransformed Hair Health
With consistent use alongside K18 Mask, hair undergoes molecular-level restoration. Strands feel thicker, more elastic, and visibly healthier. Reduced need for frequent trims.
70% reported overall hair transformationRatings by platform
11K+ REVIEWSPros & cons
BALANCEDPraised
- Incredibly lightweight and non-greasy — even fine hair loves it
- A little goes a very long way (1-3 drops is enough)
- Silicone-free formula won't cause buildup
- Clinically proven 24-hour frizz control and 104% shine boost
- Heat protection up to 450°F protects during styling
- Works on all hair types — straight, wavy, curly, coily
- Allure Best of Beauty winner; Clean at Sephora certified
- Patented K18PEPTIDE™ for molecular-level repair
Criticized
- Expensive at $65 for only 30ml (1 fl oz)
- Fragrance may be too strong for scent-sensitive users
- Contains fragrance allergens (limonene, linalool, cinnamal)
- Not enough moisture for extremely dry or very coarse hair alone
- Best results require pairing with K18 Mask (additional cost)
- Small bottle size doesn't feel like good value initially
Budget-friendly alternatives (dupes)
DUPESAlso silicone-free and uses hemisqualane as the base. Provides similar shine and smoothing benefits but lacks the K18PEPTIDE™ for internal molecular repair. Larger 50ml bottle for less than half the price.
Contains dimethicone (silicone) and Olaplex's Bis-Aminopropyl Diglycol Dimaleate for disulfide bond repair. Good heat protection and shine, but silicone-based and targets only one bond type vs K18's broader repair. 30ml size.
Argan oil-based hair oil with dimethicone. Great for adding shine and smoothness, but contains silicone and has no bond-repair technology. More of a cosmetic finisher than a treatment oil. 25ml size.
Comparison with competitors
SIDE-BY-SIDE
JVN Complete Nourishing Shine Drops
Kérastase Première Repairing Gloss Oil
Storage & shelf life
12 MONTHS12 months after opening
Store in a cool, dry place away from direct sunlight. Keep cap tightly closed. No refrigeration needed.
Glass dropper bottle with pipette for precise dispensing. Amber-tinted to protect against UV degradation.
Yes — 30ml is well under the 100ml TSA/airport liquid limit. Compact glass bottle fits easily in carry-on.
Frequently asked questions
FAQUse with caution. The K18 Hair Oil does not contain retinoids, salicylic acid, or hydroquinone. However, it does contain fragrance (parfum) and fragrance allergens including cinnamal, limonene, and linalool. While the product is applied to hair (not skin or scalp directly), pregnant and breastfeeding individuals should consult their healthcare provider before use, especially if they have heightened fragrance sensitivity.
No, this product is not considered fungal acne safe. It contains avocado oil (rich in oleic acid) and sunflower oil, both of which contain fatty acids that can feed malassezia yeast. If you're prone to fungal acne on your scalp or forehead, avoid letting the oil contact those areas. Apply strictly to mid-lengths and ends only.
Yes. Since K18 Molecular Repair Hair Oil is a hair care product (not skincare), it does not interact with skincare actives like retinol, vitamin C, AHA, or BHA. You can safely use this hair oil in conjunction with any skincare routine. It can also be layered with other hair treatments and styling products.
K18 Hair Oil is designed for all hair types — straight, wavy, curly, and coily, and all textures from fine to thick. It performs exceptionally well on damaged, bleached, or color-treated hair. Fine-haired users particularly appreciate its weightless formula, while curly and coily hair types benefit from its frizz-fighting and shine-boosting properties. It's most transformative on hair that's been through chemical processing.
You'll see instant results after the very first use — improved shine (clinically proven 104% improvement), reduced frizz, and smoother texture. For deeper molecular repair benefits from the K18PEPTIDE™, cumulative results build over 4-6 weeks of consistent use. The more damaged your hair is, the more dramatic the initial results tend to be.
Apply to damp, towel-dried hair from mid-lengths to ends after shampooing (and after K18 Mask if using both). Wait 4 minutes for peptide repair benefits before styling. You can also apply 1-2 drops to dry, styled hair as a finishing oil for extra shine and frizz control. It works before blow-drying, flat-ironing, or air-drying.
K18 Hair Oil has a low comedogenic rating of 1/5. It's designed to be applied to hair (mid-lengths to ends), not directly to the skin or scalp. With proper application, pore-clogging is not a concern. However, if the oil comes into contact with your forehead or neckline, it's worth noting that avocado oil can be comedogenic for some individuals (rated 0-3 depending on the person).
K18 Molecular Repair Hair Oil has a PAO (Period After Opening) of 12 months. Since the formula is highly concentrated and you only need 1-3 drops per use, a 30ml bottle typically lasts 3-6 months with regular use, well within the shelf life window. Store in a cool, dry place away from direct sunlight to maximize longevity.
Verdict: K18 Molecular Repair Hair Oil is a standout in the premium hair oil category thanks to its patented K18PEPTIDE™ technology, which goes beyond surface-level smoothing to deliver real molecular repair. The silicone-free, lightweight formula works beautifully across all hair types without weighing hair down, and the clinical results (104% more shine, 78% split end reduction, 24-hour frizz control) are backed by real third-party studies. Its only significant drawback is the premium price — at $65 for 30ml, it's notably more expensive than competitors like Olaplex No. 7 and JVN Shine Drops. However, the concentrated formula means a little goes a long way. Best for anyone with damaged, color-treated, or frizz-prone hair who wants genuine repair, not just cosmetic coating.
Product Overview
What are Quick Product Notes?
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.
Pro Tip Alert!
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
Paraben-Free
Paraben-Free
Understanding Parabens
Parabens are a large group of preservatives which are used to prevent bacteria growing in cosmetic formulations. There has been some healthy controversy surrounding them due to a few studies finding paraben presence in breast tumours and breast tissue. However, the majority of the scientific community have deemed these findings non-conclusive due to the limitations of these studies. There's still a lot of support for avoiding parabens following the better safe than sorry route. If you do we completely support you! If you are concerned about the health safety of parabens, then feel free to avoid them by looking out for the Paraben-Free icon. If not, don't worry about it - they do have had one of the longest safety records as preservatives!
Which Ingredients are classified as Paraben?
A product will be paraben-free if it does not contain any of the following parabens:
- Sodium Isobutylparaben
- Sodium Ethylparaben
- Sodium Butylparaben
- Propylparaben
- Isopropylparaben
- Isobutylparaben
- Sodium Propylparaben
- Butylparaben
- Ethylparaben
- Sodium Methylparaben
- Methylparaben
Sulfate-Free
Sulfate-Free
Understanding Sulfates
Sulfates are a large group of ingredients which act as cleansing agents in Cosmetics. They help loosen up the dirt and grime from your skin and hair to allow for water to wash it away with ease. However some sulfates are so good at their job, they can wash off your skin’s own natural oils that keep it moisturised and protected which can lead to dryness and irritation. Most people will find no issues with sulfate, however if you find your skin doesn't like sulfates then free feel to avoid them by looking out for the sulfate-free icon on Skincarisma.
Which ingredients are classified as sulfates?
We've taken the Sulfates which are considered more harsh for our Sulfate-Free status. A product will be Sulfate-Free if it does not contain any of the following Sulfates:
- TEA-Dodecylbenzenesulfonate
- Ammonium Laureth Sulfate
- Sodium Lauryl Sulfate
- PEG-15 Cocamine
- Sodium Laureth Sulfate
- Sodium Cocoyl Sarcosinate
- Sodium C14-16 Olefin Sulfonate
- Dioctyl Sodium Sulfosuccinate
- Ammonium Xylenesulfonate
- Ammonium Lauryl Sulfate
- Sodium Xylenesulfonate
- Sodium Myreth Sulfate
- Sodium Lauryl Sulfoacetate
Alcohol-Free
Alcohol-Free
Understanding Simple Alcohols
Alcohol ingredients are widely used in cosmetics and come in different types. For the most part alcohols are not problematic at all. However one type of alcohols, simple alcohols can be quite drying to the skin because it evaporates very quickly. This can cause irritation which can also lead to other skin complications. These alcohols should never be used alone on your skin, but combined with other cosmetic ingredients, they are normally without issue. However, for some people with sensitive and easily irritable skin, avoiding products with these simple alcohols may be beneficial. If you find your skin doesn't like these simple alcohols, then free feel to avoid them by looking out for the Alcohol-Free icon.
Which Ingredients are classified as Alcohol?
A product will be alcohol-free if it does not contain any of the following alcohol ingredients:
- SD Alcohol
- Alcohol Denat
- Isopropyl Alcohol
- Alcohol
Silicone-Free
Silicone-Free
Understanding Silicones
If you've ever used a skincare, makeup or beauty product that's made your skin look and feel smoother tempoarily - it's likely contained Silicone. They are a popular class of ingredients found in cosmetics due to their smooth, soft, easy-to-spread and smooth properties that help creates an artificial layer/barrier on top of skin or hair (commonly found in conditioners).
For the same reasons they are popularly used, they are also commonly avoided. Anecdotally, many individuals have reported that Silicones cause/excerbate breakouts, irritation, cause a feeling of skin being unable to breathe, cause clumping of cosmetic products and find it difficult to wash off. As a result, those who find them problematic are avoiding them and increasingly, cosmetic companies are avoiding them as well.
If you have had bad experiences with Silicones in the past, or suspect they are problematic then look out for the tick on the Silicone-free label.
Disclaimer
The Silicone-free label only includes the most common Silicone ingredients that have indentified been reported by individuals that could potentially cause issues.
These include: Amodimethicone, Behenoxy Dimethicone, Bis-Aminopropyl Dimethicone, Cetearyl Methicone, Cetyl Dimethicone, Cyclomethicone, Cyclopentasiloxane, Dimethicone, Dimethicone Copolyol, Dimethiconol, Methicone, Phenyl Trimethicone, Phenyl Trimethicone, Stearoxy Dimethicone, Stearyl Dimethicone, Trimethylsilylamodimethicone.
Note, that this does not include all ingredients part of the Silicone class of ingredients.
EU Allergen-Free
EU Allergen-Free
Understanding the Identified Contact Allergens
The EU's Scientific Committee on Consumer Safety (SCCS) has identified and established 26 cosmetic ingredients that are likely contact allergens (potential to cause skin allergies) as demonstrated in clinical or epidemiological studies. The EU's SCCS have recommend cosmetic companies to disclose them on the labels if used and in cases where the concentration exceeds 0.001% in leave-on products and 0.01% in rinse-off products, then they must be labelled.
Look out for the tick on the EU-Allergen free label to know your cosmetic is free from any of the 26 identified cosmetic ingredients.
For more information regarding the EU's Scientific Committee on Consumer Safety, please visit their official website.
Disclaimer
The EU Allergen Free label is for the 26 ingredients identified by the EU SCCS and products will be only flagged if a suspected ingredient is on it's ingredient list. It is possible for cosmetics to contain one of the suspect ingredients without it appearing on the ingredient list due to it not reaching the concentration threshold to disclose it and cosmetic manufacturers choice to not disclose it.
Also note, the EU Allergen Free label is not personalized for your own allergies you may have and it does not constitute as medical advice. For your specific case, always consult your medical professiona such as dermatologist, physician, pharmacist, or health care provider - please read our medical disclaimer for more information.
Fungal Acne (Molassezia) Safe
Fungal Acne (Molassezia) Safe
Understanding Fungal Acne (Pityrosporum Folliculitis/Malassezia Folliculitis)
Pityrosporum Folliculitis/Malassezia folliculitis or simply known as Fungal Acne is a persistent acne-like condition that commonly responds poorly to traditional acne-treating methods. Unlike most cases of Acne where bacteria is the culprit, Fungi is the culprit of Fungal Acne (Hence the name!). There are certain classes & groups of ingredients that have been shown to promote and feed the growth of the Fungal Acne, Fungi such as fatty acids, oils, esters, polysorbates and fermented ingredients.
For more information regarding Fungal Acne, please visit Simple Skincare Science (f.c) - #3 of our Recommend Skincare Resources for an amazing comprehensive guide!
Please Read: How to use the Fungal Acne (Malassezia) Label
At SkinCarisma, we've done our best to identify as many ingredients as possible but note the fungal-free label may not be 100% accurate due to the complexconditions and combination of ingredients that malezzeria can thrive on.
Additionally, products that may contain ingredients that have shown to feed Malassezia may not neccessarily exacerbate the condition due to concentration of ingredient used in the product, this information is simply not available on the products.
As a result, please note this is only an experimental label that can be best used to possible identify problematic products you have used in the past. It is in no way a perfect identifier nor a predictor in whether or not it will exacerbate or cause fungal acne. It will continue to be worked on as more information and research comes to light.
If you find any ingredients you believe should be included, please email us at snails@skincarisma.com.
Disclaimer
Due to the lack of substantial research into this area it is very likely there are other ingredients and class/groups of ingredients that could feed Fungal Acne which have not been indentified.
The Fungal-Safe label does not constitute as medical advice. For your specific case, always consult your medical professiona such as dermatologist, physician, pharmacist, or health care provider - please read our medical disclaimer for more information.
What are Notable Effects & Ingredients?
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.
Pro Tip Alert!
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
Anti-Aging from 1 ingredient(s):
Promotes Wound Healing from 1 ingredient(s):
What are Ingredients Related to Skin Type?
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.
Pro Tip Alert!
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
Dry Skin
Oily/Acne-Prone Skin
Sensitive Skin
What is the Ingredient Safety Breakdown?
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.
Pro Tip Alert!
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 |
|---|---|---|---|
| 0 |
Caprylyl Caprylate/Caprate
Emollient, Skin Conditioning
|
Hydrating
|
|
| 1 |
Squalane
Skin Conditioning, Emollient, Hair Conditioning, Refatting
|
Hydrating
|
|
| 0 |
Persea Gratissima Oil
Skin Conditioning
|
Hydrating
|
|
| 0 |
Helianthus Annuus Flower
Skin Conditioning
|
|
|
| 0 |
C13-15 Alkane
Solvent
|
|