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K18

K18 Leave-In Molecular Hair Mask, Repairs Dry or Damaged Hair, Reverse Hair Damage from Bleach, Color, Chemical Services & Heat

  • Based on 25,997 reviews
Condition: New
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Availability: Only 10 left in stock, order soon!
Fulfilled by Amazon

Arrives Sunday, Nov 16
Order within 13 hours and 2 minutes
Available payment plans shown during checkout

Size: 0.51 Fl Oz (Pack of 1)


Brand: K18


Item Form: Cream


Material Feature: Cruelty Free


Hair Type: All


Product Benefits: Our K18PEPTIDE™ repairs hair at a molecular level across multiple types of bonds, restoring hair health for all See more


Product Dimensions ‏ : ‎ 1.37 x 1.37 x 3.18 inches; 1 ounces


Item model number ‏ : ‎ BP94620800


UPC ‏ :


Manufacturer ‏ : ‎ K18


Best Sellers Rank: #156 in Beauty & Personal Care (See Top 100 in Beauty & Personal Care) #2 in Hair Treatment Masks


#2 in Hair Treatment Masks:


Customer Reviews: 4.3 4.3 out of 5 stars 25,997 ratings


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, Nov 16

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Is there are any more to be said than what’s been said already?
Size: 50 ml
Because of the insane price, I put off buying the full size until I had used the trial size and knew it was worth my money. It is!! I did the 6 consecutive treatments, followed by one approximately every 4-6 weeks, and the health of my hair has improved dramatically. I had some troubleshooting errors originally, as having thick, long, curly hair makes it almost impossible to not use a conditioner. However, after about 4 uses and a lot of research, I started to wait the 4 minutes and follow up with a conditioner, and that’s when I felt my hair start to feel amazing. The damage is reduced, there is significantly less breakage and shedding, and I am looking to buy the jumbo size once this is finished. It is now a staple in my routine despite the cost simply because of the effectiveness. ... show more
Reviewed in the United States on October 13, 2025 by Jaime

  • OMG! OMG ! OMG! K-18 FULFILLS ITS CLAIMS Read on!
Size: 0.51 Fl Oz (Pack of 1)
I’m over 55 and have spent decades trying everything — from $9 to $144 per product — hoping for softer, healthier hair. I have 3a curls hidden under years of color, heat damage, and dryness. My hair would break and frizz so badly it looked like I had layers (I don’t). K18 is the first and only product that actually delivered on its promise to repair — not just coat — my hair. I was fully prepared to return this if it did not make a difference. It did. This isn’t a conditioner or mask. K18 uses a patented technology that works from the inside out. I used a clarifying shampoo, applied 6 pumps (very small pumps from the "try it" bottle!), finger-raked it through damp hair, waited 4 minutes, and then combed through. No rinsing, no other products. I let my hair air-dry, and it already felt softer and smoother with significantly less frizz. No fragrance -makes me happy. Important note: You do not need to rub this aggressively between your palms to "activate" it — that’s a common myth. Just rub your palms lightly so you can apply it evenly and let the science do the work. It works on the keratin molecules to repair your hair from the inside out. Friction is not going to make the molecules smaller. Don't know why people start these rumors. The next morning, I used my straightener on medium heat and was stunned. Instead of the usual dry straw, my hair was sleek, shiny, and bouncy. Even the ends curled beautifully — something I’ve never seen on my hair before. After four treatments, my hair now feels different, although the greatest results came after the very first use. My hair is softer, smoother, more manageable, with less frizz and more shine. Even in Florida’s 90°+ heat and humidity, it holds up — and I’m not using anything else but K18. A friend even asked to try it after seeing my results. It’s expensive, but absolutely worth it. I’ve already bought the larger bottle. I’m sticking with K18 — this changed everything for me. And to address the expense, the 50mL pump provides 50 pumps. That's 25 applications for me. My average thickness, long hair uses 2 full regular pumps. After the first 4 applications, you move to every 4 washes. That means after the first four treatments, I have 21 treatments more still in the pump bottle. For me, with super dry hair, that means it will last another 18-21 weeks since I only wash once a week, and an occasional "extra". I am going to guess I have taken at least $100 of products that did not work for me to the women's shelter over that time, meaning the waste was as much as this effective product that takes no time to use, packs easily in a suitcase, doesn't stink and IT WORKS! If you have super straight, silky hair, like Asian hair, or other non-porous hair, I do not think you are going to get the same results. You probably already have the kind of hair those of us with porous, damaged hair are looking for. Ask ChatGPT ... show more
Reviewed in the United States on June 25, 2025 by GG

  • Fixed My Bleached Hair in One Use – Actual Hair Resurrection
Size: 50 ml
LITERALLY SAVED MY HAIR IN ONE USE – MIRACLE IN A BOTTLE I don’t usually leave reviews, but I would actually fight someone over this product if it ever got discontinued. Like. That’s how serious I am. I bleached the living life out of my hair recently—think straw, think crunchy ramen noodle ends, think “oops I fried it but I still want it to look good.” I used K18 once, and I swear to god my hair looked like I had never damaged it at all. ONE USE. Not three. Not six. One. This isn’t your average deep conditioner or protein mask. This is full-on biotech magic. The science behind it is real—this isn’t marketing fluff. It uses a patented peptide (K18Peptide™) that literally reconnects broken polypeptide chains in your hair. Like, it doesn’t just make your hair feel soft temporarily. It rebuilds it. We’re talking actual molecular repair. You feel the difference IMMEDIATELY. And even better? The results just get better the more you use it. No rinsing, no long routines. You just shampoo, skip conditioner, towel-dry, use 1–3 pumps depending on your hair length, and then wait 4 minutes. THAT’S IT. It absorbs fast, isn’t heavy, doesn’t make your roots oily, and doesn’t coat your hair in a waxy film like other products. My hair went from stringy and dead to soft, bouncy, shiny, and fully alive again. Also? A little goes a long way. It’s expensive, yeah, but it lasts forever and genuinely does what it says. I’d rather spend money once on something that works than keep buying cheap products that do nothing but mask the damage. TL;DR – If your hair is damaged from bleach, color, heat, or just life, BUY THIS. It’s not hype. It’s not overrated. It’s the best hair product on the planet and deserves to be in every single “best of” list forever. I’ve tried Olaplex, I’ve tried everything—nothing touches this. K18 is THAT GIRL. ... show more
Reviewed in the United States on May 27, 2025 by Christopher E Christopher E

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