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molecular repair hair oil
before + after k18 routine and oil
model with molecular repair hair oil
78% reduction in split ends
one use of molecular repair hair oil delivers: clinically proven damage repair, 24-hr frizz control, 104% more shine, 78% reduction in split ends, and 450F heat protection
highly concentrated formula. start with 1-3 drops, build as needed.
silicone-free weightless oil is powered: K18PEPTIDE(TM), Avocado Oil, Sunflower Oil, Hemisqualane + Squalane.
how damage + frizz related? before + after of outer and inner layer
are you using K18 mask today?
K18 vs other oils
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model image
molecular repair hair oil formula
Molecular Repair Hair Oil
best seller

K18 molecular repair hair oil

Weightless oil that strengthens, repairs damage + reduces frizz
Rated 4.7 out of 5
Based on 483 reviews

This biotech-engineered weightless oil works on all hair types to strengthen, repair damage, reduce frizz at two levels of the hair fiber, and improve shine.

  • clinically proven damage repair
  • 24-HR frizz control
  • 104% more shine
  • 78% reduction in split ends
  • 450°F (232°C) heat protection
OR
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Strengthening, smoothing hair oil works on two levels of the hair fiber to fight frizz.

The K18PEPTIDE™ works to address deeper-level damage that causes frizz—repairing and strengthening damage at the innermost layer of hair to reverse damage that leads to frizz.

On the surface of hair, natural oils like avocado and sunflower oil, and hemisqualane and squalane nourish while smoothing frizz + flyaways to improve color vibrancy, enhance shine, and provide 450°F (232°C) heat protection.

  • Clinically proven to repair damaged hair*
  • 24-HR frizz control*
  • 104% increase in shine*
  • 78% reduction in split ends*
  • 450°F (232°C) heat protection*

*Disclaimers

This silicone-free oil fights frizz differently by addressing the damage that causes frizz long-term and immediately smoothing frizz + flyaways.

  • Reverses frizz-causing damage: Works at the molecular level to repair damaged hair, which is more susceptible to frizz
  • Reduces frizz + flyaways: Natural oils work on the surface of the hair to smooth the cuticle + soften without weighing hair down
  • Enhances shine + color vibrancy: Nourished, moisturized hair reflects higher shine and boosts color dimension
  • Delivers heat protection: to prevent further frizz-causing damage up to 450°F (232°C)

Apply to damp, towel-dried hair before styling, or on dry hair as a finisher. Highly concentrated formula. Start with 1-3 drops and build as needed.

Use on damp hair for: strengthening benefits and to reduce frizz during air-dry or styling

Use on dry hair to: smooth frizz and flyaways, as a finisher to add shine

  • Apply to damp hair from mid-lengths to ends. For strengthening benefits from the K18PEPTIDE™ wait 4 minutes before styling.
  • Apply to dry hair as a finisher.

Pro Tip - If using the K18 molecular repair mask, apply the mask first on clean, damp hair, then wait 4 minutes. Apply the molecular repair hair oil, and wait 4 minutes for maximum strengthening results.

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.

pairs well with

full-size leave-in molecular repair hair mask

Rated 4.6 out of 5
Based on 7555 reviews
4-minute leave-in treatment to reverse hair damage

Description

This biotech-engineered weightless oil works on all hair types to strengthen, repair damage, reduce frizz at two levels of the hair fiber, and improve shine.

got questions?

Get started here.

We recommend using the oil with the mask for maximum molecular repair with additional styling benefits. Think of the mask as a damage repair treatment after washing your hair. The oil is for smoothing, styling and strengthening after the mask, and can be used on damp and dry hair.

Yes, this oil provides heat protection up to 450°F/232°C.

No, it will not leave buildup or weigh down your hair. This weightless oil is powered by intentional ingredients to reduce frizz-causing damage on the molecular level inside the hair fiber, while natural oils work on the surface of hair without weighing it down.

Plus, you don’t need much of this highly concentrated formula to see results, just use 1-3 drops and build as needed. If you’re concerned about buildup, use our detox shampoo to remove 99% of product buildup after just 1 wash*.
*Disclaimers

No, the mask will not block the molecular repair hair oil from penetrating. The mask is a highly concentrated treatment without any fillers so it won’t block the oil from penetrating. Like layering different skincare products, the oil can be layered on top of the mask without impacting its performance.

Instead of mixing the oil and mask together, get the most effective repair and styling benefits by using the mask first, waiting 4 minutes, and then applying the oil.

how to use it

PRO stylist + educator Carly Zanoni shows you how to apply the molecular repair hair oil.
PRO stylist + educator Eric Vaughn shows you how the K18 leave-in molecular repair hair mask + oil work together in your routine.
molecular repair

hair oil vs. mask

Do you use one over the other? Both? Glad you asked! Both are meant to be used at different parts of the routine but were created to work together for maximum impact
molecular repair oil
what it is: weightless, silicone-free hair oil

what it does: reverses damage that causes frizz long-term while immediately smoothing flyaways, adding shine, and reducing split ends

when to use: on damp or dry hair throughout styling
molecular repair mask
what it is: leave-in treatment

what it does: reverses hair damage in 4 minutes for lasting + progressive results

when to use: after shampoo, on damp, towel-dried hair before styling

the K18 difference

Feel what’s possible with fewer steps, less waste + less time.
efficacy
patented K18PEPTIDE™ powers deeper + lasting repair.
simplicity
fewer steps for a streamlined routine.
speed
results in one 4-minute use.

how molecular repair compares

how K18 works

Traveling into the innermost layers of hair, our K18PEPTIDE™ renews strength along the width AND length of hair for lasting strength where it matters.

reviews

average rating 4.7 out of 5
Based on 483 reviews
  • 5 Stars
    407 Reviews
  • 4 Stars
    41 Reviews
  • 3 Stars
    15 Reviews
  • 2 Stars
    8 Reviews
  • 1 Star
    12 Reviews
93% of reviewers would recommend this product to a friend
Customer photos and videos
483 Reviews
Reviewed by Earlene P.
Verified Buyer
hair oil sample
Reviewing
hair oil sample
I recommend this product
Rated 5 out of 5
Review posted

Shine That Lasted

My hair had to shine and it lasted into the next day so I think I’ll order this. Five stars from me. I don’t have a second photo before I used it.

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K18Hair

Thank you for your review Earlene!

Reviewed by Kelsie C.
Verified Buyer
hair oil sample
Reviewing
hair oil sample
I recommend this product
Rated 5 out of 5
Review posted

Love!

I love that this doesn’t make my hair greasy and that I can use it daily!

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K18Hair

Thank you for your review Kelsie!

Reviewed by Amanda W.
Verified Buyer
I recommend this product
Age
35 - 44
Client Hair Concerns
  • Chemical Damage
  • Heat Damage
  • Color Care
  • Frizz
  • Fragile/Brittle Hair
Client Hair Types
  • Medium Density
  • Thick/Coarse
  • Straight/Wavy
  • Curly/Coily
  • Grey Hair
Client Results
  • Less Frizz
  • Stronger hair
  • Less Breakage
  • Soft Touchable Hair
  • Shinier Hair
Rated 5 out of 5
Review posted

Perfect for blondes

This lightweight oil doesn't just make hair feel fabulous, it heals it all the way down to the cortex layer. The clear color males it perfect for blondes:)

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K18Hair

Thank you for your review Amanda!

Reviewed by Kaya E.
Verified Buyer
hair oil sample
Reviewing
hair oil sample
I recommend this product
Rated 5 out of 5
Review posted

Hydrating and healing

I think this product worked great with hydrating my hair , used with other k18 products, I am a strong believer that my hair has been repaired!!!

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K18Hair

Wow look at those results! Thank you for your review Kaya!

Reviewed by Rhonda B.
Verified Buyer
I recommend this product
Age
55 - 64
Hair Concern
  • Chemical damage
  • Heat damage
  • Frizz
Hair Type
  • Thick/Coarse
My Results
  • Less Frizz
  • Bouncy Hair
  • Smoother Hair
  • Soft Touchable Hair
  • Shinier Hair
Rated 5 out of 5
Review posted

Silky Not Greasy

I love the Molecular Repair Hair Oil. It makes my hair feel very healthy and silky without feeling greasy. I love the dropper because you only need a very small amount to cover your hair. I use it before and/or after I dry my hair.

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K18Hair

Thank you Rhonda! We appreciate your review!

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