Weak, brittle nails are a serious hassle. It can hurt when they break, and knowing they might crack or split at any moment can get in the way of your daily activities. And of course, you probably find that they don’t look great, especially if you’re trying to grow out your nails or play around with nail polish.
If you’re looking for a nail strengthener, you’ve come to the right place. We’ve selected the best ones on the market — focusing on nourishing treatments to improve nail flexibility and prevent breakage. We also included nail hardener polishes to reinforce your nails, along with sets, nail oils, and more. Are you ready for some reinforcement?
Best nail strengthener overview
- Best overall: Onyx Brands Hard as Hoof Nail Strengthening Cream
- Best budget: Vaseline Intensive Care Healthy Hands Stronger Nails Lotion
- Best splurge: ISDIN Si-Nails
- Best hardenere: OPI Nail Envy
- Best budget hardener: Sally Hansen Diamond Strength
- Best treatment: CND RescueRxx
- Best clean: Ella+Mila First Aid Kiss (Nail Strengthener)
- Best oil: Barefoot Scientist Inner Strength
- Best color: ORLY Breathable Treatment + Color
- Best duo: Nailtopia Nails Are Strong Kit
- Best for hands and nails: BIODERMA Atoderm Hands & Nails
- Best set: Nail Tek Restore Damaged Nails Kit
- Best base coat: NAILS.INC NailKale Superfood Base Coat
How we chose the best nail strengtheners
To compile this list, we looked through the published research behind nail strengtheners as well as manufacturer specifications to create a short list of the top nail strengtheners. Then, we combed through detailed product descriptions, ingredients, ratings, and reviews to find the best nail strengthener for each category.
Our picks for the best nail strengtheners
The best place to start when you need to strengthen your nails is with a cream rather than a brush-on nail hardener. That’s because nail brittleness is strongly associated with nail plate dehydration and oil depletion.
This thick, rich cream is loaded with nail-fortifying ingredients, including coconut acid, jojoba oil, and silk protein. You can rub the thick texture into your nails easily, and the formula contains just the right amount of water to hydrate without oversaturating the nails. It’s also incredibly affordable, so give it a try if your nails chip or split easily. That said, it may not be ideal for overly flexible or soft nails.
Active ingredients: Petrolatum, mineral oil, hydrolyzed keratin | Frequency of use: Daily as needed | Size: 1 oz
This ultra-affordable hand and nail cream promises results within just two weeks, conveniently improving nail strength while moisturizing your hands. The main ingredients are petrolatum and mineral oil, which maintain water in the nail and ensure better flexibility and resilience. Since it’s a lotion, the formula is quite light, although some reviewers found it runny.
Active ingredients: Petrolatum, mineral oil, hydrolyzed keratin | Frequency of use: Daily as needed | Size: 3.4 fl oz
ISDIN invested a lot of effort into clinical research for this formula, which includes mastic gum — said to improve keratin synthesis — and hyaluronic acid, which boosts nail hydration. As such, it’s no surprise that this treatment is quite expensive. ISDIN promises results in as little as 14 days, although this product is designed for long-term effects. The built-in brush is a convenient touch that makes application a breeze.
Active ingredients: Mastic oil, hyaluronic acid | Frequency of use: Daily | Size: 0.08 fl oz
From trusted salon brand OPI, this nail hardener polish is among the most popular on the market, with thousands of positive reviews. Like a shell, it creates a seal over the nail that adds some structure and support. It’s the immediate protection you need if your nails feel weak and soft.
In addition to sealing the nails, the formula also offers an attractive sheen, and it can double as a base coat. That said, nail hardeners like Nail Envy are largely protective. We don’t think they’re the first thing to reach for when your nails show signs of brittleness, but they’re still useful. You’ll also want to note the formula contains formaldehyde resin, which can be irritating. If that’s a concern for you, there’s also a Nail Envy sensitive formula.
Active ingredients: Calcium, hydrolyzed wheat proteins | Frequency of use: Daily for 1 week | Size: 0.5 fl oz
If you’re looking for a budget hardener, Diamond Strength is a classic that dramatically hardens the nails. This formaldehyde-free nail strengthener stops nail cracking and peeling with the help of micro-diamonds and titanium. One coat is enough, and it doubles as a base coat quite nicely. Just note that this ultra-tough formula isn’t ideal if your nails are brittle and lacking in flexibility.
Active ingredients: Microdiamonds, titanium | Frequency of use: 1 coat as needed | Size: 0.45 fl oz
This oil-based nail treatment nourishes and fortifies the nails. It’s made with sweet almond oil, keratin, and a little bit of water, so it’s more comprehensive than oil alone. It’s even backed by CND’s clinical testing, which showed less nail peeling and splitting within four weeks of twice daily use. It’s a little pricey, but it’s worth it if you want a highly effective yet lightweight oil.
Active ingredients: Hydrolyzed keratin, almond oil | Frequency of use: Twice daily | Size: 0.5 fl oz
If you prefer clean nail care formulas free from controversial ingredients, Ella+Mila offers some of our favorite options. This nail strengthener is free from toluene, formaldehyde resin, and 15 other chemicals clean beauty enthusiasts prefer to avoid.
Instead, it has a simple, protective formula enhanced by antioxidant vitamin E. Some reviewers, however, noted that it can peel after a few days of wear.
Active ingredients: Vitamin E | Frequency of use: Once daily for 2 weeks, then every other day | Size: 0.45 fl oz
This lightweight blend of sunflower seed, jojoba, and other plant oils will help condition your nails and seal in moisture. There’s celery extract in the blend — reported to offer a nail smoothing and thickening effect — as well as tea tree oil, which may help prevent fungus proliferation. While this nail oil alone can’t hydrate your nails, you can use it after washing your hands or in addition to hand cream.
Active ingredients: Celery seed extract, sunflower seed oil, jojoba oil, tea tree oil | Frequency of use: 1 drop daily or as needed | Size: 0.68 fl oz
Strengthen and color your nails all with one product. This one-step polish formula creates a breathable protective layer over the nails while also imparting color and shine. This argan and vitamin B5-infused formula is available in a plethora of shades, so you don’t need to compromise on your style. This formula doesn’t require a top coat or base coat, although some reviewers found that it didn’t last as long as regular polish.
Active ingredients: Argan oil, pro-vitamin B5, vitamin C | Frequency of use: Not specified | Size: 0.6 fl oz
This adorable, budget-friendly duo features a hardening polish and a hydrating revitalizer. It’s the perfect combo to restore moisture and flexibility while sealing and fortifying the nails. The revitalizer is the standout product here, with a hydrating, humectant-infused formula.
The strengthener is free from controversial ingredients, which clean beauty lovers will enjoy, although both formulas include a fragrance that some reviewers didn’t like.
Active ingredients: Spinach, AHA, PHA | Frequency of use: Once a day for oil, twice a week for strengthener | Size: 0.17 fl oz each
While thick, greasy creams are ideal for the nails, they’re not necessarily the most pleasant. If you’d like something light and nonsticky that you can comfortably use on both your hands and nails, this is the cream to choose. It hydrates the nails and hands with glycerin, while shea oil nourishes them. The light texture is ideal for the day, but you may want a richer nail cream at night.
Active ingredients: Glycerin, shea oil | Frequency of use: Daily as needed | Size: 1.67 fl oz each (2 pack)
This budget-friendly kit includes a few products to restore and strengthen your nails. It comes with Foundation 2, a ridge filler that acts as a fortifying base coat; Intensive Therapy 2, a hardener that protects and supports soft or peeling nails; and Renew, a nourishing nail oil made with safflower, sweet almond oil, and tea tree oil.
You can use this set alone or apply your favorite nail polish between the ridge filler and nail hardener. The only thing missing from this kit is a cream or treatment that’ll hydrate the nails directly.
Active ingredients: Safflower oil, almond oil, tea tree oil | Frequency of use: Daily | Size: 0.5 fl oz each
Most brands suggest using their nail hardener as a base coat, but it often means sacrificing some of your polish’s longevity. Not so with this formula. On its own, it supports the nails with keratin and kale extract while offering a gorgeous shiny finish.
As a base, reviewers raved that it helped their nail polish last longer, although some mentioned they found it less powerful as a hardener. Clean beauty lovers will enjoy it since it’s a 21-free formula.
Active ingredients: Keratin, kale extract | Frequency of use: Twice on first day, then once daily for a week | Size: 0.47 fl oz each
Tough as nails
There are a few different approaches you can take to strengthen your nails. The best nail strengtheners are creams like Onyx Brands’ Hard as Hoof Nail Strengthening Cream. These formulas load the nails with moisture and prevent breakage far more effectively than other approaches. That said, it’s not the only option — using a few types of nail strengtheners and hardeners will likely give you the best results.
How to pick the right nail strengthener for you
When choosing the best nail strengthener for you, keep in mind the condition of your nails and let that direct you toward the right ingredients.
Nail conditions
Weak nails are caused by a whole range of factors: overwashing, nutritional deficiencies, age, prolonged wear of nail extensions, fungal infections, and certain health conditions like psoriasis. When choosing cosmetic nail strengtheners, pay special attention to how your nail weakness manifests.
Brittle nails that chip easily are often lacking in lipids and moisture. They become less flexible, which makes them chip more easily. That’s when nail strengthening treatments like Onyx Brands’ Hard as Hoof Nail Strengthening Cream are a must.
According to Sci-Hub, soft, overly-bendable nails will benefit more from the protective effects of a nail hardener polish like OPI Nail Envy. Some people, however, may need to speak to their doctor to identify the underlying cause of nail brittleness.
Ingredients
For most brittle nail conditions, look for moisturizing ingredients that improve nail flexibility. The ideal formula will include water, water-attracting agents (e.g., glycerin, hyaluronic acid), and moisture-sealing oils.
Oils on their own can be great immediately after washing your hands. Some experts believe that jojoba oil, in particular, is best for the nails, but we haven’t seen research to confirm this.
Polish-based hardening ingredients are made with film-forming ingredients like nitrocellulose or formaldehyde resin, creating a hard external layer over the nail to prevent breakage and dehydration. However, they also increase the nail’s rigidity, so these formulas aren’t ideal if your nails chip easily due to a lack of flexibility.
You’ll frequently find hydrolyzed proteins, especially keratin, in many nail strengthener formulas. The nails themselves are made of keratin, so it’s believed that adding broken-down keratin or other proteins can help fortify them — however, this hasn’t been well researched, and it’s possible that proteins are beneficial simply because they have a hydrating effect.
FAQ
What’s the best way to strengthen fingernails?
The best way to strengthen your nails is to take a multifaceted approach. Keep your nails moisturized at all times, use a nail hardener polish intermittently when they’re feeling too soft and thin, and wear gloves when cleaning or washing dishes to avoid dehydrating your nails. Finally, don’t neglect your health, and make sure your diet includes a lot of different nutrients.
What’s better, a nail hardener or a strengthener?
These cosmetic terms aren’t well-defined, but most nail hardeners are generally considered nail strengtheners. Strengtheners are a broad category that includes polish-like formulas as well as oils, serums, and creams. The term nail hardener only refers to polish-like formulas and is ideal if your nails aren’t just brittle but also soft and overly flexible.
What deficiency causes brittle nails?
Biotin deficiency is strongly associated with nail brittleness, which is why biotin supplements are so frequently recommended for thickening the nails. That said, other deficiencies can also lead to brittle nails, including those associated with iron, cysteine, zinc, and magnesium. We recommend speaking to your doctor to find out if you have any deficiencies before taking any supplements.