K18 has beauty fanatics going wild for its high-end hair products, from the £48 dry shampoos (Space.com) to the £65 finishing oils (Cultbeauty.co.uk). The brand’s leave-in molecular repair hair mask (£70, Spacenk.com) is hugely popular, with claims that it’s superior to Olaplex No. 3, one of the most popular choices for long-lasting damage reversal.
K18’s leave-in promises to reduce split ends, breakage and colour dulling in as little as four minutes. These claims hinge on the brand’s trademarked K18peptide, which aims to produce both instant and ongoing results.
As we all know, products that truly get the job done – whether a fine line-minimising anti-ageing cream or the do-it-all tool behind your bouncy blow-dry – can feel worth their astronomical prices (ahem, Dyson). Then again, if there were an affordable alternative that actually worked, I’ve no doubt we’d be flocking to buy it. That’s why I was so happy to find a genuine alternative.
Aussie styling brand Hairification launched in the UK in May this year and, in the months since, its H24 complex leave-in repair hair mask (£10.99, Boots.com) has caused a frenzy, with the budget formula selling out earlier this month. The two hair masks look incredibly similar, and have similar ingredients, but a huge £59 price difference. It seems like there’s no way Hairification could stand up to the luxury product, so I decided to compare the two head-to-head.
How I tested
Testing over multiple washes over two weeks, I followed the Hairification and K18 instructions for application and passed one to three pumps through freshly shampooed hair, brushing the product through my strands before blow-drying as usual. Feeling the texture of my hair both wet and dry, I tested both formulas by these criteria:
- Detangling: Given that both formulas take the place of a traditional in-shower conditioner, I looked to see how easy it was to rake my usual hair brush through my hair without tugging.
- Volume: As someone with heavy hair, nourishing conditioners can weigh down my hair, so I compared the effect the two leave-ins had on the height (any flatness or extra bounce) around my roots and mid-lengths.
- Smoothing: I don’t colour my hair and never have, but I do suffer mid-strand breakage from heat damage, so I was keen to establish which mask worked better to minimise any fluffiness.
- Shine: Everyone lusts after glossy hair, so I compared the shine between the two products.
- Split ends: One of the key components of both repair creams is their ability to restore fragile hair. Though I couldn’t speak for their performance from a dye brightening perspective, I did closely analyse the state of my split ends before and after my series of K18 and Hairification treatments.
Why you can trust IndyBest reviews
Lucy Smith is IndyBest’s beauty writer, covering everything from Olaplex dupes to the Babyliss Dyson alternative. She’s spoken to hair stylists and trichologists about the best itchy scalp treatments and is constantly on top of the latest formulas and buzzy ingredients (think: rosemary scalp oils and carb-infused leave-in conditioners). Below, she puts K18 and Hairification’s repair masks through their paces. Read her review below.
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Hairification H24 complex leave-in repair mask
Key ingredients: Peptides, strengthening and shine-enhancing chia extract, growth-boosting olive leaf, wheat protein, panthenol/provitamin B5, cetrimonium chloride (a lighter alternative to behentrimonium chloride), vitamin E, fragrance
Size(s): 50ml
Vegan and cruelty-free: Yes, both
Why we love it
- Effortless smoothing
- Easy detangling
- Leaves roots lightweight and clean
- Mid-lengths and ends appear more succinct
Take note
- Not instantly effective on split ends
I went into my Hairification test somewhat sceptical. It’s not that I don’t love a budget beauty item; it’s more that I review hundreds of products each year and, when it comes to hair, I’ve often found that you get what you pay for. That said, I can’t stress it enough: buy this hair mask.
After using this several times, I can confidently say that I understand the hype and the reason why it’s been out of stock. For £10.99, you’re not only taking home the same ingredients as K18’s formula – peptides, wheat and vitamin E – but you’ll avoid the heaviness from K18’s behentrimonium chloride. It’s worth noting that those prone to extreme dryness might prefer the inclusion of behentrimonium chloride in the K18 iteration. However, if you’re prone to flat or lacklustre hair, Hairification’s switch to cetrimonium chloride will be the lightweight alternative you’ve been searching for. I experienced the same (if not more) gloss, softness and cohesion from root to tip without either build-up or heaviness.
The mask feels slightly more serum-like than K18’s, but from a damage point of view, my ends felt miraculously similar to the day they were last cut (two months ago). In fact, my hair was left with a fresh-out-the-salon finish after one use, looking bouncy, silky and thoroughly de-frizzed.
The only drawback against the more expensive K18 formula is that this isn’t as effective on heat-damaged split ends. K18 appeared to fix them all after one use, whereas this formula only worked on split ends of around half a centimetre. However, you’d have to be a professional or a pedant to notice.
There’s definitely not enough of a difference between the two products to warrant a £59 price gap. If you want a restorative hair mask, this is the one.
Read more: This shampoo and conditioner start at £3.33 a bottle - here’s why they’re my favourite
Buy now £10.99, Boots.com
K18 hair leave-in molecular repair hair mask
Key ingredients: K18peptide, behentrimonium chloride (also featured in Olaplex No.5 conditioner), thickening and strengthening wheat proteins and starches, vitamin E, fragrance
Size(s): 15ml, 50ml (pictured)
Vegan and cruelty-free: Yes, both
Why we love it
- Hair feels stronger to the touch
- Visibly volumising
- Effectively takes the place of an in-shower conditioner and post-wash styling spray
Take note
- Easy to overdo it and cause product build-up
- Expensive
It’s no surprise that K18’s repair mask is so popular. As mentioned above, the formula combines peptides, wheat, vitamin E and a conditioning ingredient called behentrimonium chloride to work on boosting hair cell turnover, strengthening strands and leaving a glossy finish. I don’t have a lab to examine the effectiveness of the cell turnover component, but I certainly felt as though my hair had more structural integrity, something which can happen when collagen and keratin increase as a result of increased cell turnover.
The mask has a thick texture similar to a traditional conditioner. My hair comes down to my shoulders, so I opted for one pump before increasing to two when my wet hair still felt a little dry.
It was easy to comb through my notoriously knotty hair without pulling. After blow-drying, I was impressed by the apparent thickness of my fine-medium density hair and, with this fullness in mind, I can certainly vouch for the benefits of the wheat starch. My fingers didn’t glide through my dry hair as freely as they brushed on towel-dried hair, but its appearance was glossy and looked undeniably healthy.
However, this glossiness meant that my hair needed another wash by the end of the following day, so I’d argue that the formula is better suited to thicker or coarser textures. That said, I did notice improvements to the state of my split ends, with typically heat-damaged strands – fringe and face framing pieces – looking noticeably less frazzled.
It’s very effective. It leaves hair velvety soft and saves time conditioning in the shower. It just takes a bit of trial and error to figure out your personal product ratios.
Buy now £70.00, Spacenk.com
Which is the best leave-in repair mask, K18 or Hairification?
As a long-time K18 fan, I have to give it to Hairification. I think the results from its complex leave-in are better than its luxury competitor for £60 less.
That’s not to say that K18’s molecular repair mask is ineffective. It’s not, and, on the contrary, it remains one of the best hair revitalisers on the market. But Hairification’s H24 formula undercuts it on not only price but finish, ease of use and – marginally – restoring results.
The only thing to bear in mind is that these results are specific to my straight, fine-to-medium-thickness hair, so this might not be true for everyone. In the end, however, I think there’s a clear choice between the two masks.
Looking for more hair help? Take a look at our tests of the best hair masks
