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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 model image model image

mini molecular repair hair oil

Weightless oil that strengthens, repairs damage + reduces frizz
Rated 4.7 out of 5
Based on 434 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
Full Size - $65.00 30 mL Mini Size - $27.00 10 mL
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more to know

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

key benefits

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)

how to use

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.

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.

pairs well with

full-size leave-in molecular repair hair mask

Rated 4.6 out of 5
Based on 7462 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.

Can i use the molecular repair hair oil instead of the mask?

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.

Does the molecular repair hair oil provide heat protection?

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

Will the molecular repair hair oil leave buildup or weigh down my hair?

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

Will the mask block the molecular repair hair oil from penetrating?

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.

Can I mix the oil and mask together?

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.
molecular repair oil, in action
  • damage
  • dryness
  • split ends
  • damage: hair before and after using molecular repair hair oil
  • dryness: hair before and after using molecular repair hair oil
  • split ends: hair before and after using molecular repair hair oil
  • damage
    clinically proven damage repair*
    24-HR frizz control*
    104% more shine*
    78% reduction in split ends*
    450°F (232°C) heat protection*


    *Disclaimers
    **after K18 routine + oil - K18 detox shampoo, molecular repair mask, oil on damp hair, blow dry, oil on dry hair

how to use it

  • how to use the oil
  • how to use the oil + K18 mask together
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
Please select a size
Full Size - $65.00 30 mL Mini Size - $27.00 10 mL
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
Please select a size
Full Size - $75.00 50 mL Mini Size - $29.00 15 mL

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
Write a Review
average rating 4.7 out of 5
Based on 434 reviews
  • 5 Stars
    365 Reviews
  • 4 Stars
    38 Reviews
  • 3 Stars
    13 Reviews
  • 2 Stars
    7 Reviews
  • 1 Star
    11 Reviews
93% of reviewers would recommend this product to a friend
Customer photos and videos
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434 Reviews
Reviewed by R F.
Verified Buyer
mini molecular repair hair oil
Reviewing
mini molecular repair hair oil
I recommend this product
Age
65+
Hair Concern
  • Fragile/brittle hair
  • Dryness
  • Heat damage
  • Frizz
  • Color-care
Hair Type
  • Thick/Coarse
My Results
  • Less Frizz
  • Visible Difference
  • Smoother Hair
  • Shinier Hair
  • Oil absorbed
Rated 5 out of 5
Review posted

The best!

This oil made my hair feel less dry and not oily at all.

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K18Hair

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

K18 Hair Oil

The hair oil really sleeks and shines with no residue! Love this stuff ♥️

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K18Hair

Thank you for your review!

Reviewed by Kath
Verified Reviewer
Molecular Repair Hair Oil
Reviewing
Molecular Repair Hair Oil
I recommend this product
Age
18 - 24
Hair Concern
  • Heat damage
  • Frizz
Hair Type
  • Curly/Coily
My Results
  • Less Frizz
  • Stronger Hair
  • Visible Difference
  • Less Breakage
  • Defined Curl/Wave Pattern
Rated 5 out of 5
Review posted

Changed my life (not even being dramatic)

I got this after loving the hair mask, I have curly hair but it’s been damaged by heat for so many years (especially as a teen) and i could never imagine wearing my hair natural because it just looked bad like frizzy, curls were not good. I’ve tried so many shampoos and creams for curly hair but this oil takes the frizz to zero and my curls look decent - I don’t know what it did compared to others on the market but i can finally feel comfortable enough to wear my natural hair. AND IT MAKES IT SO SOFT!

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K18Hair

Thank you for your review!

Reviewed by Kelly W.
Verified Buyer
Molecular Repair Hair Oil
Reviewing
Molecular Repair Hair Oil
I recommend this product
Age
45 - 54
Client Hair Concerns
  • Heat Damage
  • Split Ends
  • Dryness
  • Oily hair/scalp
  • Fragile/Brittle Hair
Client Hair Types
  • Thick/Coarse
  • Medium Density
  • Curly/Coily
  • Grey Hair
  • Straight/Wavy
Client Results
  • Cleaner, fresher hair
  • Visible Difference
  • Stronger hair
  • Shinier Hair
  • Smoother Hair
Rated 5 out of 5
Review posted

Hair Oil

The oil has a pleasant smell , it’s lightweight, the shine is nice however I’d love to see it as a spray !?

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K18Hair

Thank you for your review!

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

Awesome product

I could tell after one use the change in my hair

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K18Hair

Thank you for your review Sherry!

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