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

Bleach blonde hair before and after results using k18.

Red curly hair before and after results using k18.

dark coily hair before + after styling with k18 hair products.

Grey curly hair before and after results using k18.

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

Mini versus full size product comparison

best seller

4.8

Rated 4.8 out of 5 stars

858 Reviews

K18 molecular repair hair oil

Name: Molecular Repair Hair Oil
Brand: K18Hair
SKU: K18-32011
Price: 65.00 USD
Availability: InStock
Rating: 4.8 (858 reviews)

Weightless oil that strengthens, repairs damage + reduces frizz

Molecular Repair Hair Oil $65.00

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.

clinically proven damage repair
24-HR frizz control
104% more shine
78% reduction in split ends
450°F (232°C) heat protection

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.

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).

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

4.7

Rated 4.7 out of 5 stars

8,427 Reviews

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4.6

Rated 4.6 out of 5 stars

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Interdimensional biotech reverses bounce-depleting damage for 2-day hold

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.

immediate + lasting frizz control

Boost shine and seal split ends on all hair types—weightlessly.

before

after

"I normally don't use hair oils as my hair gets naturally oily....I loved the end result! I will officially be adding this hair oil to my routine"
- Fabiola N.

before

after

"I use this alllll the time. It's truly saved my hair....And it's so gorgeous and shiny and the thickness is returning nicely." - Emma L.

before

after

"It makes my hair much smoother after it’s been so damaged."
- Crystal A.

before

after

"So far so good, used it around 4 times and my hair looks shinier and has less frizz"
- Anel

clinically proven smoothness

hour frizz control*

more shine*

reduction in split ends*

degree heat protection*

how to use molecular repair oil

Highly concentrated formula. Start with 1-3 drops and build as needed.

1. Apply 1-3 drops to towel-dried hair from mid-lengths to ends.

2. For strengthening benefits from the K18PEPTIDE™, wait 4 minutes before styling.

3. Apply 1-3 drops to dry hair as a finisher.

learn more on our blog

The best way to use hair oil

While there’s no exact “wrong” way, there is a better method.

FUNdamentals 33: What’s in our molecular repair hair oil?

You know what's FUN-damental? When your product works. We'll be breaking down key info + recommendations to help you get the most out of K18.

FUNdamentals 32: How do I use the molecular repair hair oil?

You know what's FUN-damental? When your product works. We'll be breaking down key info + recommendations to help you get the most out of K18.

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Tips, tricks, and common misconceptions

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See how K18 unlocks our community's expression

4.8

Rated 4.8 out of 5 stars

Based on 858 reviews

Reviews Summary

Customers say this hair oil delivers exceptional results with just a few drops. Many reviews highlight its lightweight formula that works well for both fine and thick hair types. The oil effectively tames frizz and flyaways while adding softness and shine without feeling greasy. Users particularly appreciate how it smooths dry ends and works well on various hair textures. While most find it highly effective, some mention the scent is noticeable and a few note the price point is high. Common feedback emphasizes that a small amount goes a long way, making the product last longer than expected.

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858 reviews

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Hope L.
Verified Buyer
Reviewing
hair oil sample
I recommend this product
Rated 5 out of 5 stars
2 days ago
Amazing
I’m officially obsessed k18 took my dry, brittle, over processed hair and made it feel silky smooth and just.. brand new
Was this helpful?
K
K18Hair
Yesterday
It's amazing how the molecular repair technology can make such a dramatic difference in over-processed hair. Thank you for sharing your experience with us!
Amanda B.
Verified Buyer
Reviewing
hair oil sample
I recommend this product
Rated 5 out of 5 stars
6 days ago
Hair oil
This product instantly takes frizz away and makes damaged hair look healthier.
Was this helpful?
K
K18Hair
5 days ago
We’re so happy it’s helping reduce frizz and improve your hair’s health! Thank you for leaving us a review, Amanda!
Sanja T.
Verified Buyer
Reviewing
hair oil sample
I recommend this product
Rated 5 out of 5 stars
1 week ago
Healthier hair
This product help my hair look shiny and healthy
Was this helpful?
K
K18Hair
1 week ago
Thank you for your review, Sanja!
Diana M.
Verified Buyer
Reviewing
Molecular Repair Hair Oil
I recommend this product
Age 25 - 34
Client Hair Concerns Heat Damage, Color Care, Chemical Damage, Split Ends, Dryness
Client Hair Types Fine/Thin
Client Results Stronger hair, Visible Difference, Less Breakage, Soft Touchable Hair, Smoother Hair
Rated 5 out of 5 stars
1 month ago
El mejor aceite
Soy máster stylist de la compañía bellami y recomiendo ampliarmente el aceite k18, lo aplico para ayudarme a difuminar el cabello natural con las extensiones, protege el cabello sin dejarlo grasoso y ayuda a controlar el frizz.
Was this helpful?
K
K18Hair
1 month ago
¡Muchas gracias por esta increíble reseña de 5 estrellas, Diana!
Savannah H.
Verified Buyer
Reviewing
Molecular Repair Hair Oil
I recommend this product
Age 25 - 34
Hair Concern Frizz, Fragile/brittle hair, Dryness, Chemical damage, Split-Ends
Hair Type Fine/Thin, Straight/Wavy
My Results Less Frizz, Bouncy Hair, Stronger Hair, Less Breakage, Defined Curl/Wave Pattern
Rated 5 out of 5 stars
1 month ago
Hair Oil
I bought this to use after I use the k18 detox shampoo, then the k18 molecular repair hair mask after the shower, then this oil 4 minutes later. That’s how they recommend using this system. It’s worked well for me so far. I’m done with my initial 6 washes. I feel like my hair is a lot stronger than it was before. I’m not as afraid of it breaking on me. My hair also looks wavy more effortlessly than before. It looks like it’s healthy and not weighed down with hair products!
Was this helpful?
K
K18Hair
1 month ago
It's wonderful to hear that you're loving the complete system and seeing such amazing results with stronger, healthier-looking hair, Savannah! Thanks for this amazing 5-star review!

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K18 molecular repair hair oil

Description

Description

The best way to use hair oil

FUNdamentals 33: What’s in our molecular repair hair oil?

FUNdamentals 32: How do I use the molecular repair hair oil?

The definitive guide to drying your hair

The science of hair drying