Search  for anything...
K18

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

    • Based on 22,841 reviews
Condition: New
Checking for product changes
$29.00 Why this price?

Buy Now, Pay Later

As low as $7 / mo
  • – 4-month term
  • – No impact on credit
  • – Instant approval decision
  • – Secure and straightforward checkout

Ready to go? Add this product to your cart and select a plan during checkout. Payment plans are offered through our trusted finance partners Klarna, PayTomorrow, Affirm, Afterpay, Apple Pay, and PayPal. No-credit-needed leasing options through Acima may also be available at checkout.

Learn more about financing & leasing here.

Selected Option

Free shipping on this product

30-day refund/replacement

To qualify for a full refund, items must be returned in their original, unused condition. If an item is returned in a used, damaged, or materially different state, you may be granted a partial refund.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

Availability: Only 10 left in stock, order soon!
Fulfilled by Amazon
Arrives Wednesday, May 7
Order within 18 hours and 13 minutes
Available payment plans shown during checkout

Recently Viewed

Size: 0.51 Fl Oz (Pack of 1)


Brand: K18


Item Form: Cream


Material Feature: Cruelty Free


Hair Type: dry, 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 ‏ : ‎ 3.15 x 1.57 x 1.57 inches; 1 ounces


Item model number ‏ : ‎ K18-31007


UPC ‏ : ‎


Manufacturer ‏ : ‎ K18


Country of Origin ‏ : ‎ USA


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Wednesday, May 7

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.

  • Klarna Financing
  • Affirm Pay in 4
  • Affirm Financing
  • Afterpay Financing
  • PayTomorrow Financing
  • Financing through Apple Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Similar Products

Top Amazon Reviews

    • Really works.
Size: 0.51 Fl Oz (Pack of 1)
Lives up to the hype. I've heard a lot about K18 but was skeptical. It's getting warmer and more humid where I live and my hair gets frizzy in high humidity so I thought I'd give this a try. I used it this morning after my shower and it really does work. My hair feels soft, is nice and shiny and there is no frizz. It is light weight and smells good. I only used 4 pumps on my hair that is just above shoulder length. It is a little pricey to me but it seems to be worth it. I will likely buy this again - but maybe I'll just use it in the summer when my hair gets frizzy. ... show more
Reviewed in the United States on April 5, 2025 by A. Sparks
    • Believe the hype
Size: 0.51 Fl Oz (Pack of 1)
I was honestly kind of expecting this to be one of those TikTok-viral, snake oil products. But my hair has become less shiny and healthy as I’ve aged (I’m 57) and it has recently started to break off. I did a google search and found this product and decided to give it a try. I’m so pleasantly surprised! First of all, it’s simple to use. But more importantly, the results are fantastic! It has no strong smell and it doesn’t weigh my hair down. My hair is smooth and shiny and even has more volume. It looks so healthy and “younger”. It’s expensive, but I think I’m going to have to make room for it in my beauty budget! You don’t use regular conditioner when you use this product, so that will help offset the cost (because my regular conditioner is expensive too). ... show more
Reviewed in the United States on April 14, 2025 by JLR67
    • K18 Hair Mask – My Go-To for Soft, Strong Hair
Size: 50 ml
The K18 Molecular Repair Hair Mask is by far my favorite K18 product. I’ve used it multiple times before, and each time my hair feels softer, stronger, and healthier. It’s lightweight but highly effective, and I love how it repairs my hair without weighing it down. The Detox Shampoo and Molecular Repair Hair Mask are the only ones that really worked for my hair. Unfortunately, the regular shampoo, conditioner, and oil didn’t work for me—they left my hair dull and dry. But these two are worth the hype and have earned a spot in my routine. ... show more
Reviewed in the United States on April 4, 2025 by Roxi
    • Savior
Size: 0.51 Fl Oz (Pack of 1)
I cannot rave enough about the K18 Hair Mask—it has truly saved my hair! I used to pull my hair every day, causing so much damage and breakage. My hair was dry, brittle, and lacked any real shine or strength. After using this mask for a few weeks, the difference is incredible. The formula is super easy to apply, and a little goes a long way. I’ve noticed my hair feeling softer, looking shinier, and overall much healthier. The breakage has dramatically reduced, and the texture has improved—my hair feels stronger and more manageable. It’s as if the mask has repaired the damage I caused over time. I now look forward to hair care days because I can actually feel and see the difference. If your hair has been through a lot, this mask is a game-changer! It’s well worth the investment, and my hair has never looked or felt better. Highly recommend! ... show more
Reviewed in the United States on December 31, 2024 by nicole
    • A must for chemically treated or bleached hair
Size: 0.51 Fl Oz (Pack of 1)
Expensive but so worth it if you have chemically treated or bleached hair. I was worried it would feel thick or greasy but it just made my hair feel and look soft, shiny and healthy. Super easy to apply and light weight while being deeply nourishing. I applied more than suggested and still, my hair soaked it up. My hair stylist actually commented on how healthy my hair felt recently and I attribute it entirely to k18 ... show more
Reviewed in the United States on April 13, 2025 by emily
    • One use made a difference
Size: 0.51 Fl Oz (Pack of 1)
Yes, the bottle is TINY. However, I noticed a difference after one use! It says to skip conditioner, use the K18, wait 5 minutes, then add your hair products and style as usual. But with as thick as my hair is, I don’t skip conditioner. I’ve been blonde for years and went back to my black roots. Used black box dye to cover up the random grays that would come through and got tired of that so started going back lighter. I got balayage and it ruined my hair. Tbh I don’t think the hair stylist knew what she was doing but that’s besides the point. My hair was falling out in huge clumps through out the day and when washing and brushing. The K18 has helped with the damage, added shine back to my hair, and lessened the amount of hair that falls out. There’s not much of a scent to the product. It’s light weight. I use more than 4 pumps too. I use about 8-10 pumps. My hair is THICK and half way down my back length wise. I use this once a week and so far it’s been almost a month and I still have plenty left in the bottle. It’s worth a try if your hair is damaged from bleach 👌🏼 ... show more
Reviewed in the United States on March 22, 2025 by Lindserellyy
    • Fall in love with K18 for lots of $ LOL
Size: 50 ml
I fell in love with the K18 Leave-In Molecular Hair Mask about a year ago after my hairdresser introduced me to it. While it’s on the pricier side, its effectiveness and quality make it worth every penny. When I’m unable to splurge, I turn to my regular leave-in spray, Perfect 10 Lite. As someone with thin, color-treated hair that tangles easily and suffers from damage, this product has been a game changer. It shortens my shower time, extends the life of my conditioner, makes brushing my hair effortless, and leaves my hair looking healthy once styled. I recently purchased the larger size, fully aware of the cost. However, when I opened my package, I briefly thought I either ordered the smaller size by mistake or received the wrong item. I realized it was indeed the larger size I ordered and I debated returning it. The true test came when I woke up with a legit rat's nest. I was so thankful I had this product on hand, as it made detangling much easier than previous times when I had nothing to help with the mess. One note: I read a review suggesting that you should rub the product between your palms to activate it before applying it to your hair. That makes sense, and I’ll definitely give it a try. However, I find it quite unethical that the company leaves this step out of the instructions on the box and bottle. It feels like they might not want you to use it correctly so that you’ll need to buy more sooner—quite disappointing! ... show more
Reviewed in the United States on October 7, 2024 by Amazon Customer
    • Was hoping I’d hate it, but I LOVE it 😭
Size: 0.51 Fl Oz (Pack of 1)
It is pricey but effective. The first time I used it, I was confused because it doesn’t feel effective right away. But WOW it made a huge difference in my hair, which is super damaged from both years of bleach and also a perm. My hair is less frizzy, softer, and more manageable when I use this. I did shampoo only, no conditioner. Then the K18. At that point my hair is already feeling good. If I add a tiny bit of oil, it is absolutely perfect. Feels like I never abused it. 10/10 ... show more
Reviewed in the United States on April 1, 2025 by jenny

Can't find a product?

Find it on Amazon first, then paste the link below.