My 4-Week Hair Journey With K18​

It seems like K18’s Leave-in Molecular Repair Hair Mask exploded in popularity overnight. Suddenly it was all over TikTok and Instagram with celeb stylists and beauty influencers alike singing its praises.

Why It’s Beloved: The K18 mask reverses hair damage in just 4 minutes. With continued use, you can see strength, softness, smoothness, and bounce that gets better over time.

As someone who frequently dyes and heat styles their hair, I simply had to try it. So I decided to keep a one-month diary to see if K18 lives up to the hype! Here’s how it went:

Week One

I ordered the full-sized bottle for $75 (this highly-concentrated formula means you need less to do more. Plus, you can snag 15% off if you subscribe so I didn’t mind the upfront cost). It arrived in the cutest box with easy-to-understand instructions, and I couldn’t wait to add K18 to my routine.

It’s best if you use the K18 mask every wash for the first 4-6 washes, and then move to maintenance mode.

Before my first application, I shampooed like usual but skipped conditioner to clear the path for K18’s biomimetic peptide. I towel dried my hair ‘til damp and applied just 1 pump of K18 to start. It helped to spread the treatment between my hands so I could see where I was applying it. That was the perfect amount for my hair, but you can add up to 3 pumps total if needed.

Then you simply wait four minutes before combing and styling as usual so the mask can do its thing.

I let my hair air dry naturally, scrunching my hair to turn my waves into curls (note: K18 works on the molecular level where all hair is the same, so it will work for all hair types including curly-coily hair!) When it dried, I was impressed. My hair felt softer + looked smoother, so far so good! But do these results really get better with continued use? Let’s see…

Week Two

By week two, I was convinced it wasn’t a coincidence. My hair was definitely stronger, healthier, and feeling less damaged. I like to straighten it occasionally, but since my hair had gotten crispy, I put that hairstyle on hold…until now. After seeing my heat-damaged hair renewed with K18, I broke out my flat iron and went to town.

With a middle part, I finally got that insanely sleek, 70s disco look I’d been craving, but had never been able to accomplish before. I took SO many selfies!

After frying my hair with bleach, I was hesitant to dye my hair again. But with K18 in the picture, my hair was strong enough to try again. So I booked a hair appointment with my stylist to go lighter! Yay!

Week Three

My hair looks smoother + bouncier than it has in years! How was this possible?

K18 uses patented peptide technology to reconnect broken keratin chains at the innermost layers of hair, So instead of my hair just looking and feeling healthy, K18 renews my hair’s core strength + elasticity!

The results are noticeable, and my hair FEELS amazing.

Week Four

When I went to my hair appointment, my stylist was seriously impressed! My hair was so healthy, she told me normally we’d do this in multiple stages, but my medium brown hair could definitely handle blonde, plus some super blonde money pieces in the front!

I was so excited, and with regular K18 usage, my hair color can stay vibrant for longer with less damage. Woah. I still had so much product in the bottle, too; a little really does go a long way.


I’m kind of speechless. This stuff works better than anything I’ve ever tried, and, believe me, I’ve been experimenting with my hair my whole life.

Not only does it work, but it’s

  • An amazing value for how many applications you get
  • Perfect size for travel
  • Cruelty-free & vegan
  • Easy to add to any routine

Honestly, it’s a perfect hair product. It gives you a free pass to experiment with your hair as much as you want. And if that’s not your style, it’s an easy way to get healthy, gorgeous hair. Count me in as a subscriber for life!

JUST FOR YOU: Our friends at K18 are giving readers 10% off + FREE shipping to new customers! Follow this link to shop!

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