No. 05
in hair
// glowrecs.com/k18-leave-in-mask
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How it works.
60% would recommend
Why we ranked it No. 5 in hair
Sample
38 redditors with explicit opinion · 23 positive · 8 negative · 7 neutral
Score
0.639 — formula: 0.75 × % positive + 0.25 × pos/neg ratio
Confidence95% CI: 45–74% · the true approval rate falls in this range with 95% statistical confidence
Verdict
Recommended — ≥50% positive. Mixed but more good than bad.
Sources
r/BeautyBoxes, r/MakeupAddiction, r/MUAontheCheap, r/Wavyhair, r/curlyhair
K18 · hair
Recommended
Leave In Mask
r/BeautyBoxesr/MakeupAddictionr/MUAontheCheapr/Wavyhairr/curlyhair
TL;DR — Reddit consensus
Bond repair mask makes bleached, color-treated hair soft and frizz-free with once-weekly use. Some find it drying over time or not worth the steep price.
What redditors love
+
Makes color-treated, frizz-prone hair very soft with weekly use
“The K18 is a must as it makes my color treated hair that is prone to frizz, very soft”
u/Livid_Meeting5114 · r/Makeup →
+
Full-size bottle lasts 18 months with microscopic amounts
“I use a microscopic amount so the bottle has lasted me 18 months so far”
u/alxnna · r/curlyhair →
+
Pairs with molecule repair spray to show no visible damage
“make sure to use the K18 molecule repair spray paired with its matching mask. there's no visible damage”
u/kaamehalani · r/Hair →
+
Works on bleached hair when used sparingly 1-2 times weekly
“The K18 is a must as it makes my color treated hair that is prone to frizz, very soft, s[oft] as I use sparingly and only once or twice a week”
u/Livid_Meeting5114 · r/Makeup →
What they don’t
−
Can be very drying over time with continued use
“I would avoid k18 and Pantene Sheer Volume for a while, as those can be very drying over time”
u/erickjes · r/Wavyhair →
−
Makes hair brittle if overused beyond occasional treatments
“K18 or Olaplex when it feels needed (note it can make hair brittle if overused)”
u/RhubarbCrumble007 · r/Wavyhair →
−
Not enough repair for very long bleached hair damage
“bleached and then the green on the ends. Even with the K18 it was not enough for the length of your hair”
u/Knitterific1017 · r/Hair →
COMPARE WITH
Cheaper alternative
Innersense
Hydrating Cream
→
Direct quotes
What 38 redditors actually said.
Top 6 by confidence shown — expand below for the rest. Click any to open the original on Reddit.
A
u/Art-Supply-Addiction
·
r/BeautyBoxes
Would have loved this box, don’t need anything but that lip mask and K18 are my HGs.
C
u/ChanceDimension7995
·
r/BeautyBoxes
Okay now I'm having major FOMO that I missed out!!! The k18 box was my first one and now I'm addicted!!!
F
u/Fine-Solid9892
·
r/MakeupAddiction
o put in all this work on our behalf. I’m so upset right now tho. I just bought K18 and a Keratasse product 😩 never again. I will share this to all my friends. Let’
T
u/TwoHundredPlants
·
r/MUAontheCheap
ite memory are the April Fools takeovers (Jellyfish!). My favorite deal was the K18 full size for $18 which was amazing for my hair (and has led me to repurchase it
E
u/erickjes
·
r/Wavyhair
Your hair looks thirsty for moisture! I would avoid k18 and Pantene Sheer Volume for a while, as those can be very drying over time. Gra
A
u/alxnna
·
r/curlyhair
I personally love the K18 oil (I use a microscopic amount so the bottle has lasted me 18 months so far). I
Show all 38 mentions ↓
"happier than ever.
Current Routine:
Usually a pre oil treatment or Olaplex 3 (K18 after a tax return though, you feel me??)
Head and shoulders (never 2-in-1, tho"
View thread →
"tle for at least 3 months as I use sparingly and only once or twice a week. The K18 is a must as it makes my color treated hair that is prone to frizz, very soft, s"
View thread →
"The fable and mane oil is amazing! k18 would be a good addition"
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"great! make sure to use the K18 molecule repair spray paired with its matching mask. there’s no visible damage,"
View thread →
"Curlsmith. Before I deep condition I wash well with a clarifying shampoo, I use k18 or Ouidad, to remove any buildup. I feel like buildup prevents the absorption of"
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"I didn't know I had curly hair until I started using k18"
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"i tried the olaplex, k18, and the briogeo mask from allure beauty box love them all this is so good"
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"ioner (my favorite is Redkin Extreme Bleach Recovery, or K18. I understand that K18 is crazy expensive, but it works.) Please don't judge the entire industry based"
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"questions about what products to use or things to help I’m happy to share some. K18 is great though. It’s gonna be ok! Sorry that happened but your hair will grow b"
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"OMG yes. K18 and hydration are vital. My curl pattern did loosen a bit so I have to work hard"
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"The star for me is the K18. I've never tried it before but heard great things."
View thread →
"Is there actual evidence behind K18? Why are they charging $75 while other bond builders on the market are much les"
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"antly reduced her comb out and styling. Her hair was snagging less. But on with K18...She's leary of leave in conditioners"
View thread →
"the last stubborn bits of pink out and gave me a blank canvas to redye on
- one k18 use after a clarifying wash
- one Aphogee protein treatment (once I got back hom"
View thread →
". And my waves look boingier!
My routine:
1. Bond bar clarifying shampoo
2. k18 damage shield conditioner, rinse out in shower
3. Bowl method using a little bi"
View thread →
"At least none that would make a noticeable difference to a consumer. Olaplex, K18 and all the rest play up their bond building technologies, but then include trad"
View thread →
"grow it back out, but some shape with a wave/curl will help you until then. the k18 MUST be helping because i think like the perm would have left manyyyy split ends"
View thread →
"integrity is not there. bleached and then the green on the ends. Even with the K18 it was not enough for the length of your hair. Did she make you aware of your h"
View thread →
"The only way to heal your hair would be new growth. I’d use some products like K18 or Olaplex to help bond as much as you can. You can always cut it all off down t"
View thread →
"get a fresh haircut, few days of k18 to keep it healthy, then most importantly a blow out for the event"
View thread →
"K18 leave in treatment!!!"
View thread →
"-K18"
View thread →
"f the scalp and hair thinning, but a derm telling you to apply hair oil and use k18 is a huge from any of their relevant training at best. But there are lots of oth"
View thread →
"it, but I'm looking for some bond repair I can introduce in my daily routine as K18 is bring used 1-2 times a month or a few uses after color service."
View thread →
"ame direction?
They only test the products for ONE treatment! Both olaplex and k18 are marketed as products to use overtime to see results.
They should have incl"
View thread →
"protein treatments so may be worth it occasionally to counteract bleach damage. K18 or Olaplex when it feels needed (note it can make hair brittle if overused). Cou"
View thread →
"a trim to try make it even, k18, other treatments n stuff to fix it"
View thread →
"the last picture is after two weeks of using k18. I have no idea what to do."
View thread →
"they probably olaplexed it (or something similar like k18) cut it then used products to do the style."
View thread →
"OMG! K18, Clinique, Lancôme. 😞"
View thread →
Threads tracked
The conversations we're watching.
Adjacent
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02
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03
Olaplex
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Bond-building treatment that damaged hair users rely on weekly, especially after bleach.
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