Bye Bye, Brittle Nails! We Tested Nail Strengtheners for 8 Weeks, and These 12 Actually Improved Texture and Growth

After testing 20 formulas, the CND Nail Strengthener RXx Daily Keratin Treatment is the nail strengthener that wowed us the most. This nourishing formula is enriched with sweet almond oil, so it provides strengthening perks while supporting cuticle health and ensuring nails are hydrated and flexible enough to prevent breakage. Since it’s a serum, you need to use it more frequently — similar to a cuticle oil — for the best results. However, it layers nicely under nail polish and has a fantastic brush for easy application. 

During the eight-week period, we found that our usually thin and brittle nail beds were actually much healthier-looking. Our nails not only looked and felt stronger, but our cuticle health improved, too. 

Size: 0.5 ounces | Ingredients: Sweet almond oil | Type: Serum

We were also impressed by the Nailtiques Nail Protein Formula 2 as a cheaper yet effective option. The formula contains keratin, gelatin, and calcium and is technically a polish, so you can use it as a base or top coat. We love that it’s easy to apply, fast-drying, and provides nails with a subtle shine. It also improved our nail texture, not only strengthening them but also improving weaker areas to prevent further breakage. And you only have to use it twice a week — much less than many other options we tried. 

We were a bit disappointed by the fading that occurred between uses. It also has a stronger smell, so if you have a sensitive nose, you might want to try the CND Nail Strengthener RXx Daily Keratin Treatment instead. 

Size: 0.25 ounces, 0.5 ounces | Ingredients: Keratin, gelatin, calcium | Type: Polish

This is an even more budget-friendly Amazon find. The nail-strengthening polish can either be worn as a base or top coat. Plus, it has nourishing and strengthening ingredients such as keratin and jojoba oil to support nail bed health and promote more flexibility (resulting in less breakage). You only need to apply it every three days for best results, and it dries quickly so you can easily layer it with other polish. It has a nice sheen to it, but it did peel after a few applications. All things (and under-$7 price) considered, it’s a good budget option.

Size: 0.5 ounces | Ingredients: Keratin, jojoba oil | Type: Polish

Nail strengtheners can also promote growth, and this one did. It’s a polish that’s easy to apply and relatively mess-free. It’s formulated with hydrolyzed wheat protein, hydrolyzed soy protein, and calcium to grow stronger and longer nails, and it leaves behind a shiny finish, too. When we started the test, our nails were short, brittle, and prone to splitting from wearing gel polish, but, by week four, we noticed major improvements in our nail texture, strength, and length.

Size: 0.45 ounces | Ingredients: Hydrolyzed wheat protein, hydrolyzed soy protein, and calcium | Type: Polish

Cuticles can also benefit from using a nail-strengthening formula. This effective nail strengthener uses a clinically tested MSM technology that strengthens and hydrates the nails, promoting more flexibility and keeping breakage at bay. It moderately helped improve cuticle health and was easy to apply, only needing a few coats once a week. It takes a while to dry, but it doesn’t leave behind a sticky residue. Instead, it creates a shiny, long-lasting finish that doesn’t chip or fade. 

Size: 0.46 ounces | Ingredients: MSM technology | Type: Liquid

Layering a nail-strengthening base coat into your at-home manicure routine can significantly improve results. This polish has a large applicator brush that expertly covers the nail in the base coat solution. It’s also quick-drying and non-sticky, so it layers nicely with other polish and top coats. Plus, it helped mask our nail imperfections and improved the texture overtime. While we wish this had a shiny finish for those days when you prefer a more natural manicure look, we love the formula’s subtlety. 

Size: 0.6 ounces | Ingredients: Not listed | Type: Polish

The Probelle Nail Strengthener is formulated with lots of nourishing ingredients to moisturize, revitalize, and strengthen the nail beds. It’s easy to apply and dries super fast should you want to top it off with a layer of colorful polish. We were impressed by how well it improved the look of nail texture (so smooth!) and how nicely it layered under and over nail polish. It has a stronger scent, but the formula extends the life of your manicure by a week before chipping — so it’s worth it. 

Size: 0.5 ounces | Ingredients: AHAs, vitamin B5, vitamin C, and hexanal | Type: Polish

We were delighted with how quickly this base coat dries. In our test, it dried almost instantly upon application and left behind a glossy finish. It comes with an applicator brush that improves the efficiency of swiping it across our nails, and we love that it’s formulated with vitamins A and E for added nourishment. Although the formula didn’t impact our nail growth, it worked well at smoothing out the nail bed’s surface. 

Size: 0.5 ounces | Ingredients: Vitamin A, vitamin E | Type: Polish

If you don’t mind applying a nail strengthener a few times a day, this one had a simple process thanks to the brush design and formula consistency. Despite requiring multiple daily applications for the best results, the polish was easy to incorporate into our routine. Plus, it effectively strengthened our nails which made the extra effort more than worth it. The polish also layers well with regular nail polish, so this is a great option for adding a nail-strengthening component to your at-home manicure routine.   

Size: 0.4 ounces | Ingredients: Multi-polymer technology | Type: Polish

If you want a no-frills but super effective option, reach for the Barielle Nail Strengthener Cream. This creamy formula was originally created to improve the strength of racehorse hooves and was so effective that humans started using (and swearing by) it, too. The scentless formula has a non-greasy texture, is easy to apply and, with regular wear, can improve nail strength incredibly well. You just have to commit to applying this formula at least a few times a day for the best results. 

Size: 1 ounce | Ingredients: Glycerin, vitamin E, vegetable protein | Type: Cream

This was one of the most interesting formulas we tested because it’s part nail strengthener and part nail polish. It also comes in multiple colors, so you don’t have to use a ton of products to achieve a solid at-home manicure. The polish has a wide brush for easy application, a shiny finish — it’s so shiny that you barely need a top coat — and is enriched with biotin, calcium, and vitamins A, C, and E. It has a thicker consistency, so it takes longer to dry, but it’s honestly worth the extra wait time since it’s a two-in-one formula. 

Size: 0.5 ounces  | Ingredients: Biotin, calcium, vitamins A, C, and E | Type: Polish

Need some reinforcement? This kit comes with three products: cuticle oil, strengthener, and ridge filler to repair nail health. While testing, we found that that kit actually resulted in healthier-looking nails. The application process is super easy, and the formula is quick-drying with a subtle shiny finish. The ridge filler also effectively improved nail texture, and despite there being three steps to keep track of, it was all relatively easy to use and incorporate into our routines. 

We did note the smell is a bit strong, the strengthener fades between uses, and the ridge filler requires an immediate swipe of the top coat to prevent chipping. Nonetheless, these elements work well together to revitalize nail beds. 

Size: 0.5 ounces  | Ingredients: N/A | Type: Polish