K18 Hair Product Reviews With Photos
An Honest Review of Every K18 Hair Product
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If you are even remotely interested in hair care, you've probably heard of K18. The brand's Leave-In Molecular Repair Hair Mask has amassed a cult-like following after going viral on TikTok multiple times, and massively popular influencers like Alix Earle are fans. Practically everyone who has tried it out says it's worked wonders on their hair, taking it from dry and damaged to soft and shiny.
"The secret is in the patented K18 peptide — born after 10 years of complex bioscience research — which is the perfect molecular puzzle piece to reconnect damage sites, restoring strength and elasticity," Suveen Sahib, co-founder of K18, tells POPSUGAR. Apparently, while some products condition the hair just by coating it, K18 products work at a deeper level to molecularly repair hair.
At first, the claims sounded too good to be true, and I was on the fence about testing the products out. But after months of watching my favourite influencers, coworkers, and even friends rave about the brand's products, I knew I needed to try them for myself. K18 currently has four different products on the market: their viral hair mask, a detox shampoo, a daily shampoo, and most recently, a hair oil.
I tested all of them, so keep reading to find out which products earned a coveted five-star rating.
K18 Peptide Prep Detox Shampoo
K18 Peptide Prep Detox Shampoo ($38)
I'm fairly new to detox shampoos, and the first time I tried one was when I did a hair detox recommended by TikTok. The brand recommends using this product once a week (or as needed), but because I only wash my hair twice a week at max, I use it biweekly.
I typically massage it into my head using the upside-down washing method, rinse, and then repeat. I've found it especially beneficial to use this shampoo after I've gone an extended period of time without washing my hair or if I've been wearing my hair in a style that requires a lot of product, like a slicked-back bun.
Made with activated charcoal and salicylic acid, this shampoo always leaves my hair and scalp feeling squeaky clean, and it doesn't leave my hair feeling dry or straw-like. Although it goes against my natural instincts, I'm okay skipping conditioner as long as I plan to use the brand's hair mask after.
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K18 Peptide Prep pH Maintenance Shampoo
K18 Peptide Prep pH Maintenance Shampoo ($36)
The Peptide Prep shampoo is a colour-safe product that the brand says is safe to use each time you wash your hair. I've been using this twice a week for the last few weeks instead of my regular shampoo. I massage it into my hair and scalp, rinse, and then repeat. If I'm planning to use the molecular hair mask, I skip conditioner, but if I'm not, I use one.
I've found that it's gentle on my hair and doesn't leave it feeling stripped or dry, but it doesn't leave my hair feeling as soft as I'd like, either. Plus, I'm a big fan of fragrances in my hair products because I like everything to smell good, and this scent was fairly nonexistent.
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K18 Molecular Repair Hair Oil
K18 Molecular Repair Hair Oil ($65)
The Molecular Repair Hair Oil is the newest addition to the K18 lineup, and it's already landed a permanent spot in my routine. If you're using this hair oil in conjunction with the mask, the brand recommends using the mask on damp hair first, waiting four minutes, and then applying the hair oil. From there, the brand says you should wait another four minutes before styling your hair using hot tools.
If you're using it on dry hair, the brand recommends using it as a finishing product to add shine.
I like stacking my products for maximum efficiency, so every time I use the mask, I use the hair oil as well. However, I've also used the hair oil on days when I didn't use the mask, and I still noticed benefits. The biggest difference this hair oil made was cutting down on the amount of frizz and flyaways I had on a daily basis. Plus, it offers heat protection up to 450 degrees, so I don't have to layer another product on top before using hot tools.
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K18 Leave-In Molecular Repair Hair Mask
K18 Leave-In Molecular Repair Hair Mask ($75)
Using the mask is fairly simple. Each time I tested it, after shampooing my hair, I skipped out on conditioner altogether. After towel drying it, I took a pump of the mask and rubbed it in between my hands until it looked thick and had a paste-like consistency. From there, I evenly distributed it throughout my hair using my hands, and then I brushed everything through using a wide tooth comb.
The product needs four minutes to activate, so after the four minutes, I either followed up with heat styling or let my hair air dry. On the occasions when I used it, I noticed a huge difference in the texture of my hair as well as its frizziness. Everything felt smoother, seemed shinier, and in my opinion, just looked better in general.
The brand recommends that you use the mask every three to four washes, which is the routine I've been following, and I've seen great results.
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