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K18

4.6 • 39 Reviews

K18 sells peptide hair care products to reverse hair damage.

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K18 Reviews

4.6

K18 earns strong reviews for visibly repairing damage and boosting shine and softness—especially on bleached, heat-styled, or frizz-prone hair—yet feedback is mixed on the leave-in mask’s results for healthy hair. Reviewers praise the lightweight oil, innovative AirWash dry shampoo, and fast, non-greasy finish, while noting drawbacks like potential heaviness or clumping if overused, harsh shampoos for some, residue and limited longevity from AirWash, and occasional scent and buildup concerns.

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Articles

Reviews and Posts

View all 39

  • 1mo ago

    I LOVE this hair oil. It's lightweight and leaves my hair looking smoother and shinier without feeling greasy or weighed down. A few drops are enough to help tame frizz, smooth flyaways, and add a healthy-looking finish. I also noticed that my hair felt softer and looked less dry after regular use. The formula absorbs quickly, so it doesn't leave behind an oily residue, and a little goes a long way. The only negative I will say that it smells like chlorine which isn't great, and there are a lot of unnecessary perfuming ingredients in it.

  • 1mo ago

    The K18 AirWash is one of the more unique dry shampoos I've tried, since it's not dry at all. It actually comes out in a liquid spray instead of the usual powdery spritz other dry shampoos have. I liked that it didn't leave a noticeable white cast, which made it easy to use without extra brushing or blending. The scent is fresh but not overwhelming. But I didn't feel like it quite matched the efficacy of other dry shampoos on the market.

  • 10mo ago

    The K18 Leave-In Molecular Repair Hair Mask is a standout in the “hair repair” category. It leverages a genuinely different technology (peptide-based, inside-the-strand repair) rather than just smoothing or coating hair. For the right hair conditions (damage, breakage, chemical/heat stress), it delivers visible and lasting improvement. If your hair is healthy and you just want a nice mask, you might prefer to spend elsewhere. But if you’ve been lamenting damaged ends, limp texture or persistent frizz, this product is absolutely worth the investment. Make sure you activate the product by rubbing it between your hands until it becomes opaque!

  • 10mo ago

    As someone with fine but thick oily (oily as heck!!) hair, this product is a GODSEND!! I’ve primarily used aerosol based dry shampoos and they’ve worked well, but this dry shampoo absolutely takes the cake! It doesn’t leave any white residue and it lasts forever. I sprayed just a few sprays into my hair, waited 2 minutes, and brushed and OMG it worked so well! It seriously felt like I had washed my hair!!

View all 39 reviews

What is K18?

K18 sells peptide hair care products to reverse hair damage.