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

802 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 (802 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

8,265 Reviews

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4.5

Rated 4.5 out of 5 stars

260 Reviews

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.

The definitive guide to drying your hair

Tips, tricks, and common misconceptions

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feel what's possible with K18

See how K18 unlocks our community's expression

4.8

Rated 4.8 out of 5 stars

Based on 802 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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802 reviews

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Jill M.
Verified Buyer
Reviewing
Molecular Repair Hair Oil
I recommend this product
Age 55 - 64
Hair Concern Split-Ends, Dryness
Hair Type Thick/Coarse
My Results Visible Difference, Stronger Hair, Less Breakage, Smoother Hair, Shinier Hair
Rated 5 out of 5 stars
1 week ago
Amazing!
My hair got very fried from a flat iron. This made such a difference!
Was this helpful?
K
K18Hair
1 week ago
Thank you for your review, Jill!
Marisa M.
Verified Buyer
Reviewing
Mini molecular repair hair oil
I recommend this product
Age 45 - 54
Hair Concern Dryness
Hair Type Grey Hair
My Results Smoother Hair
Rated 5 out of 5 stars
1 month ago
Smooths ends
Takes away the frizz while smoothing dry ends
Was this helpful?
K
K18Hair
4 weeks ago
Smooth hair with our Molecular Repair Oil! Thank you for your 5-star review!
Debra D.
Verified Buyer
Reviewing
hair oil sample
I recommend this product
Rated 5 out of 5 stars
2 months ago
Hair saver!
I was born blonde, and I will die blonde.
That statement took its toll on my now mid-60’s hair….it was breaking and thinning.
My stylist tried a new product on me, the K18 hair mask and hair oil. I was sold after the first use, and have gone on to use the Peptide Prep Shampoo, Hair Mist, and Conditioner. I am now the salons poster child for reclaiming beautiful hair!
Was this helpful?
K
K18Hair
2 months ago
This make us so happy to hear, thank you for your review and continued support!
Jennifer B.
Verified Buyer
Reviewing
hair oil sample
I recommend this product
Rated 5 out of 5 stars
3 months ago
Best hair oil and protection for my hair
Love this oil helps.my hair so much, I wasnt fosure about this hair oil, as I've tried many in the past! This is the best hair oil I've tried and I can't wait to buy the full-size.
Was this helpful?
K
K18Hair
3 months ago
We agree! Thank you Jennifer!
Morgan P.
Verified Buyer
Reviewing
Mini molecular repair hair oil
I recommend this product
Age 25 - 34
Hair Concern Dryness
Hair Type Fine/Thin
My Results Cleaner, fresher hair
Rated 5 out of 5 stars
3 months ago
So helpful!
Love it! So nice and healthy
Was this helpful?
K
K18Hair
3 months ago
Thank you for your 5-star review!