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10 best nail strengtheners for dry, brittle or weak nails, tested and reviewed in 2025
Your DIY mani just got an upgrade.
My nails are ridiculously brittle – like the kind of brittle that causes constant peeling and chipping. Sure, they look fine after I slap on a few coats of polish, but the majority of nail polish brands don’t do much to help your nail health (and, tbh, can actually make your weak nails even weaker – especially if you're using gel nail polish or removing your polish the wrong way).
That’s why I like to call in the A-team every so often: nail strengtheners. Yup, I’m talking about nail-strengthening polishes and treatments that help restore your damaged nail beds with vitamins, proteins, and hydrators.
Nails, while hard keratinised structures, do have absorptive capacity, explains board-certified dermatologist Karan Lal. Essentially, he says, there are two types of nail strengtheners: those that "hydrate" (hi, hyaluronic acid, butylene glycol, lactic acid, panthenol, etc.), and those that "protect" (hi, calcium, protein, biotin, etc.) by creating a film that acts as a physical shield. The key is to find a nail strengthener that is easy enough to be consistent with and addresses your specific nail concerns. As for the best brands and products? I gotchu.
Our top picks for the best nail strengtheners in 2025:
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BTW: There are so many nail strengtheners on the market right now that anyone can benefit from them, whether you’ve got naturally weak nails like me, or you just need something to counteract your gel mani habit. Plus, they’re kind of a genius way to level up your at-home spa days (just sayin'). So keep scrolling for the 10 best nail strengtheners that target everything from peeling and breaking to rough textures and dullness.
Best nail strengtheners to save your sorry nails...
Board-certified dermatologist Dendy Engelman loves this nail strengthener because it "improves fingernail thickness, strength, and durability." The reason it earns our number one spot is because its key ingredients – hyaluronic acid, and pistacia lentiscus oil –have been *scientifically proven* to significantly increase nail firmness when applied consistently over the course of a few weeks. Drops mic, adds to cart.
Hydrate or protect? Hydrate
Top coat/base coat? No
Key ingredient(s): Hyaluronic acid, pistacia lentiscus oil
Glowing Customer Review: "After using this product for almost a month I am sold. I haven't had any nails split, which was a continuous issue even with the best of nail strengtheners. The most amazing result is the ridges in my nails are diminishing. It's been years since I've had smooth nails and I'm looking forward to seeing how much the nails will smooth over."
Protein Formula Strengthen Nail Treatment
This strengthener is the best of both worlds. It contains biotin to repair damage and promote stronger nails, while glycerin and panthenol provide hydration. Call on it if your brittle nails are constantly chipping and breaking. A few coats of this every week will sort you out.
Hydrate or protect? Both
Top coat/base coat? No
Key ingredient(s): Glycerin, biotin, panthenol.
Glowing Customer Review: "After having acrylic nails on for a holiday earlier this year I was worried my nails wouldn’t ever recover. This product is amazing, it’s strengthened my nails and they are looking the best they have ever looked."
Manucurist Base S.O.S
Sensitive girlies, this one is for you. Manicurist's Base S.O.S is fortified with vitamin C and B5 to moisturise and strengthen brittle nails. It's also formulated with with 78% bio-sourced ingredients, (including sugar cane, corn, wheat and cotton) so it is just as delicate on your skin and nails as it is the environment.
Hydrate or protect? Hydrating
Top coat/base coat? Base coat
Key ingredient(s): Vitamin B5 (a humectant to retain moisture) and vitamin C (an antioxidant).
Glowing customer review: "I’m really impressed with this treatment polish. My nails are dry and peeled easily. I have used lots of other nail polishes and nothing else has worked. This polish stays on my nails well and seems to be holding the peeling layers together as they gradually grow out."
Essie Strong Start Nail Polish Base Coat
The Essie Strong Start base coat saved my nails from breakdown following back-to-back gel manis. The polish is formulated with biotin – needed to reinforce broken nails – which has worked wonders in helping to prevent peeling and breaks. It also can be used as a base coat so I can paint on my polish with ease.
Hydrate or protect? Protect
Top coat/base coat? Base coat
Key ingredient(s): Biotin and vitamin E
Glowing customer review: "This base coat provides strength and protection for nails and aids healthy growth. I have found my nails to grow faster and stronger and my nail polish to last for longer too (approx 2 weeks without any signs of chipping!)"
Orly Nail Defense
This nail strengthener is enhanced with protein to repair existing damage and make your nails more resistant to damage in the future. Use it on bare nails (you'll want to apply a fresh coat every other day), under your nail polish as a base coat, or layered over polish as a top coat.
Hydrate or protect? Protect
Top coat/base coat? Both
Key ingredient(s): Vitamin E, calcium, hydrolysed wheat protein
Glowing Customer Review: "I had fake nails for over 13 years, so I have a very hard time with peeling and soft nails; it is very difficult for nail polish to stay on my nails. This product seems to be working better than anything else I have tried."
Some nail hardeners rely on harsh chemicals, like formaldehyde, to strengthen nails, but not this formula. It’s free of 21 controversial ingredients, including DBP, xylene, and parabens, but packed with nail-fortifying ones, like biotin, vitamin B, and calcium. This base coat works to treat your nails as it primes them for polish.
Hydrate or protect? Protect
Top coat/base coat? Base
Key ingredient(s): Biotin, calcium, methiopeptide* (*an amino acid derived from keratin)
Glowing Customer Review: "I really love this base coat. It keeps the nail polish on much longer than usual. I also find that it strengthens my nails and stops the breakage. I will definitely get another bottle of this."
nails inc. Nailkale Superfood Base Coat
With ingredients like kale, lemon, and pomegranate extracts, this base coat is basically a green juice for your nails. But the real star here is the added keratin, which works to restore the protein, fight flaking, and harden your fragile fingernails.
Hydrate or protect? Both
Top coat/base coat? Base
Key ingredient(s): Keratin, vitamin E, glycerin
Glowing Customer Review: "This works amazingly well. I have tried everything on my weak, split, and peeling nails. In fact, for the past couple of years, I have taken a daily dosage of biotin and seen a dermatologist... but nothing seemed to work until NailKale. In just two weeks my nails have grown significantly; they are harder, and the ends that were split and peeling prior to use are growing out."
Sundays B.03 Nail Strengthening Base Coat
The best thing about this nail strengthener is that it also works as a base coat. Prep your nails with a couple of coats, and the formula's argan oil, amino acids, and vitamin E work to condition and harden your nails while also creating a smooth, glossy base for your polish.
Hydrate or protect? Protect
Top coat/base coat? Base
Key ingredient(s): Calcium, vitamin E
Glowing Customer Review: "The colour itself can be used for a classy sheer mani with no streaks. My nails have never been better since I used this as a base. I open boxes at my job and haven't seen much nail splitting since switching to this."
Looking for an easy way to treat your nails on this go? This strengthening pen makes things v convenient – just massage the formula on your nails and cuticles one to two times a day and it'll help bring some life back into your weak-ass nails (without needing to take off your polish).
Hydrate or protect? Both
Top coat/base coat? Neither* (*a cuticle/nail oil-like pen)
Key ingredient(s): Keratin, jojoba oil
Glowing Customer Review: "Best nail strengthener I've ever used – the pen is super easy to use. Applying once per day, I started to see obvious results in how sturdy the ends of my nails felt in just two to three days. After two weeks, I haven't had any breaks or peels. My nails and cuticles look and feel great."
Essie Nail Polish Strengthening Treat Love Colour
If you refuse to take time off between manis because you despise the look of bare nails, but your peeling, broken tips could really use some TLC, try this nail polish and treatment combo from the cult-favourite nail polish brand Essie. It has what your fragile nails need (collagen) but also all the colour and sheer coverage you want – the best of both worlds, really.
Hydrate or protect? Protect
Top coat/base coat? Both* (*and polish)
Key ingredient(s): Collagen, camellia extract
Glowing Customer Review: "Wow! I have been a nail-biter for as long as I can remember. And, once I stopped, I tried so hard to grow out my nails. I had some success, but once my nails got to a certain point, they split at the edge or peeled. I tried every nail vitamin, growth treatment, and polish I could think of. Everything changed when I started using Essie Treat, Love, & Color!"
Can nails absorb substances?
Yes, nails do have an absorptive capacity. However, some substances can penetrate your nails much easier than others. This is because nails are made of super strong keratin that acts as protection against damage that could affect the health of your nail barrier. Unfortunately, this means that strengthening ingredients (hi, calcium, protein, biotin, etc.) are likely not absorbed enough to impact your nail growth from below, says Dr. Lal.
But (but!) for the good news: Your nails are *extremely* permeable to water (hi, water-binding humectants) and oils, which are emollients that work to seal moisture in. This means that nail-strengthening products rich in oils and hydrating ingredients are great options for people who struggle with peeling, textured, hard, and/or sandpaper nails, says Dr. Lal.
As for the strengthening ingredients, although your nails are not absorbing too much of the substance, they actually do have a positive impact if you're trying to repair damaged, weak nails. This is because these strengthening ingredients provide protection (aka a film) over your natural nails, giving them the best environment to grow healthy and stronger.
How to choose the best nail strengthener:
Decide if you want a "protecting" or "hydrating" strengthener
There are two types of nail “strengtheners” – those that harden and those that hydrate. Dr. Lal breaks it down for us:
- Hydrating strengtheners contain ingredients that hold and bind water to your skin and nails. Hyaluronic acid, butylene glycol, lactic acid, and panthenol are all great examples. Some formulas may also contain lipids like triglycerides and glycerin, which moisturise your nails. Hydration-based strengtheners are great for those with peeling, textured, hard, and/or sandpaper nails.
- Protecting strengtheners rely on ingredients such as keratin, protein, biotin, and calcium, all of which add a film and allow your nails to appear stronger and thicker. These ingredients are not likely to be totally absorbed enough to impact your nails’ growth from below, but they will act as a physical shield, which prevents breakage, chipping, and cracks.
Determine if your brittle nails are due to an underlying cause
"At the end of the day, brittle and thin nails may be from genetics, poor diet, thyroid disease, anemia, or underlying diseases," Dr. Lal says. Make sure you see a dermatologist for a thorough diagnosis, as brittle nails may actually be nail psoriasis, lichen planus, or even eczema, he says. Based on the cause of nail issues, specific supplementation may be helpful and/or treatment of the underlying cause.
Consider supplementing the nail strengthener with other methods
The best and easiest tip for ensuring you maintain healthy nails is through supplementation, says board-certified dermatologist Dendy Engelman. You should be eating protein, calcium, zinc, and vitamin A in your diet and supplementing with vitamins, she adds.
Meet the expert:
- Dr Karan Lal is a board-certified dermatologist and the director of cosmetic dermatology at Affiliated Dermatology in Scottsdale, AZ. Dr. Lal specialises in pediatric and adult dermatology, laser surgery, and treating skin of colour.
- Dr Dendy Engelman is a board-certified dermatologist at Manhattan Dermatology & Cosmetic Surgery and director of dermatologic surgery at Metropolitan Hospital in New York, New York.
Why trust Cosmo?
Siena Gagliano is an associate editor at Cosmopolitan who writes beauty, with over three years of experience writing in the makeup, skin, and hair spaces. She’s an expert at researching and writing beauty stories, like the best drugstore eye creams and the best clear sunscreens. She regularly tests and analyses nail strengtheners on her own nails for efficacy while working with the industry’s top dermatologists to assess new formulas and products.
Lauren Balsamo is the deputy beauty director at Cosmopolitan with eight years of experience researching, writing, and editing beauty stories that range from laser skin tightening to the best sunscreens for oily skin. Her nail strengthener picks were based on product reviews, personal testing, and information from experts.
Lauren Balsamo is the beauty director at Cosmopolitan where she writes, edits, and produces all types of beauty content—from product reviews to personal essays and trend reports. She has covered beauty for more than a decade at Cosmopolitan. Follow her on Instagram.
Clare Stephenson is the Senior Fashion and Beauty E-commerce Writer for Cosmopolitan, ELLE and Harper’s Bazaar. She has been an e-commerce writer since 2022, creating matter-of-fact reviews and shopping pages filled with her favourite products for every budget and need – whether that’s a glow-giving foundation, a high-tech LED face mask or the perfect wear-with-everything blazer.
Alongside writing, Clare loves to be in front of the camera creating shopping content, putting viral products to the test to see which ones are truly worth the hype. Through her work, she has interviewed leading dermatologists, makeup artists and industry experts to bring readers trusted advice and product recommendations.
Clare has contributed to titles across the Hearst UK portfolio, including Women’s Health, Good Housekeeping, Red and Prima. Prior to joining Hearst, she earned a BA in Multimedia Journalism from Bournemouth University, focusing her studies on magazines and editorial. She later worked as an editorial assistant at Voir Fashion Magazine, covering events including Fashion Week and interviewing notable brand founders.
Outside of work? You can find Clare strolling through London’s Columbia Road Market, pouring her fourth coffee of the day or heading to a Pilates class.
Follow Clare on Instagram @clarefrancesstephenson.
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