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

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

This product is pricey but the results are worth it. I have continued to repurchase this product as nothing else makes my hair stronger and healthier looking than when I use K19. Stop wasting your money on less priced items that don’t work like K19.

My hair was looking pretty crappy. I remembered I ran out of this product. Got it again and within 2 uses my hair is back looking decent. I have incredibly fine hair and this does not weight it down, indeed it actually gives my hair body and makes it soft. It is easy to use. I think everyone should try it. Smells good too. Honestly, every k18 product I have tried it next level amazing.

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.

I really like this hair mask. I think it works well for chemically treated hair. It makes my hair soft. I will say the bottle is very small for the price. You don't get very much. I would like to see a better value for my money.

I have very fine long hair but lots of it and everything weighs down my hair and makes it look limp and flat. I tried everything to have well conditioned non-flat hair - the expensive products, the all natural organic products, oils, you name it. For my hair K18 just works perfect. Doesn’t weigh it down but gives it a lovely sheen and texture. I would say it’s tripled the “healthy” look of my hair in just 3 weeks. I use it just as the instructions say, just 1 pump of product. Just once a week. It’s so effective that now I don’t even use daily conditioner after I shampoo, and somehow it also keeps my hair nicely detangled. So I’m losing less hair when I comb it out. This is NOT a conditioner - it’s a strengthener. So I use it along with Olaplex no 8 which I do once a week for 10 minutes. These 2 products work well for me. But I think it all depends on the type of hair you have, everyone is different.

This product is just ok for me. I don’t notice it doing a whole lot for me. I stopped using all other hair products besides a heat protectant so I could truly get a feel for this product. My hair doesn’t feel smooth and soft like it claims. It’s still easily knotted and my hair doesn’t look any different. I went back to using my hair oil that is a leave in conditioner, makes it shine and a heat protectant and it’s $13. My hair with that feels amazing. For the price I really thought it would be a magical product and maybe I set my expectations too high. It does not weigh my hair down or make it greasy so that’s a win but that’s about all I like about it.

Hell to the yes! Okay, so I bleached the back half of my hair platinum blonde about a month ago. When I'd get that section wet, it would feel gummy. I have used Infusium spray in conditioner to get it unmatted every time I get it wet and even then, was only brave enough to use my fingers to detangle. When it dried, my hair would have no shine, individual strands had multiple hard bumps (likely areas where it was just about to break off), and only Olaplex #3 used inappropriately (as an overnight leave-in conditioner) made it a bit softer...temporarily and if it even dried. It started taking hours to dry once it was bleached, so I only washed it once a week with a sulfate-free shampoo and did so early in the day so that I didn't have to sleep on wet hair. I bought the $50 Moroccan Oil mask and the $10 Dove Intensive mask. I used these individually and my hair was so thirsty that I never even rinsed either mask out of my hair. I used them as leaving conditioners. Some days I would put straight up coconut oil in my hair (even in addition to one of the masks), and within hours, my hair had absorbed it ALL. It would be shiny and easy to brush at this point but was not something I would wear in public (because it was drenched in heavy, unstylable oil and would stain my tops). I broke down and purchased the K18 leave-in mask knowing that the bottle was small and expensive, but I figured I would only treat the damaged area and that might make it worth the investment. I received my package today and wasn't even brave enough to wash this damaged mess prior to application. I only wet it, applied the product and by the time my hair dried, my hair was unrecognizable by touch. It blended perfectly with the rest of my virgin, undamaged hair which is soft, and reflects light. The ends of each hair are still pointed straight down like a broomstick, but I mostly focused on the tangled, gummy area but I have no doubt that THIS is the holy grail that everyone is looking for. From what I understand, K18 never washes out because it permanently repairs the strands of hair. I feel $30 was worth even just this ONE treatment, but I have 90% of the bottle remaining for multiple future treatments. I suspect in the near future, $30 for the mini will be a great buy compared to what K18 could be making off of all of us desperate, DIY'ers!