When it comes to caring for damaged hair, both Olaplex and Kerastase are brands that repair and strengthen hair. But which haircare brand is better? In this post, we’ll be comparing Olaplex vs Kerastase to help you decide which hair care products are best for your needs.
First, a quick primer on the brands:
Kerastase is a luxury French haircare brand that was established in 1964. It is one of the most popular and well-known luxury haircare brands, known for its high-quality products.
Kerastase is owned by L’Oreal, one of the largest cosmetics companies in the world.
Olaplex is a newer haircare brand founded in 2014. The brand is known for its patented bond-building technology, which helps to repair damaged hair.
Olaplex has quickly become a best-selling haircare brand, boasting a #1 selling shampoo, conditioner, and hair treatment.
To make a fair comparison, it is important to look at how the products work and what issues they address. So, let’s take a closer look at Olaplex vs Kerastase:
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Olaplex vs Kerastase
How Olaplex Products Work
Olaplex vs Kerastase is a bit of a tricky comparison. Both products are designed to protect hair from damage, but they work in different ways.
Olaplex works on a molecular level to rebuild the hair from the inside out with their patented ingredient: Bis-Aminopropyl Diglycol Dimaleate.
This molecule is part of Olaplex’s bond-building technology that strengthens hair by repairing broken disulfide bonds that give hair its strength.
What contributes to broken disulfide bonds? Heat styling, color, chemicals, UV damage, frizz, split ends, dryness, and even brushing and pulling on your hair.
It penetrates the hair shaft and strengthens the bonds between the proteins in your hair.
This makes it ideal for people with damaged, dry, brittle hair, as it can help repair the damage and prevent further damage from occurring.
And the good news is that Olaplex’s bond-building technology is present in all Olaplex products.
Olaplex is formulated for all hair types, whether you have color-treated, straight, textured, or curly hair. Olaplex can even be used on hair extensions.
Olaplex at-home products are part of their multi-step haircare system. The steps are as follows:
- Step 0: Intensive Bond Building Treatment
- Step 1: Bond Multiplier (In-Salon Treatment)
- Step 2: Bond Perfector (In-Salon Treatment)
- Step 3: Hair Perfector
- Step 4: Bond Maintenance Shampoo
- Step 5: Bond Maintenance Conditioner
- Step 6: Bond Smoother Leave-In Styling Treatment
- Step 7: Bonding Oil
- Step 8: Bond Intense Moisture Mask
- Step 9: Bond Protector Nourishing Hair Serum
You don’t need to use all of their products to see great results. You can pick and choose based on your haircare needs.
We’ll discuss Step 3 Hair Perfector, Step 4 Bond Maintenance Shampoo, Step 5 Bond Maintenance Conditioner, and Step 9 Bond Protector Hair Serum in this post.
How Kerastase Products Work
Kerastase offers multiple professional haircare lines to treat damaged hair, including Genesis, which addresses hair breakage from brushing, and Resistance, which is formulated to rebuild weak and damaged hair.
In this post, we’ll look at Kerastase Resistance Therapiste damaged hair deep treatment products that treat very damaged, over-processed hair.
It reconstructs the hair fiber and heals ends by entering the hair cuticle to strengthen hair and improve hair growth.
The Therapiste line uses active ingredients like gluco peptides, a wheat protein derivative, and native plant cells to hydrate and strengthen hair and improve hair growth.
In this post, we’ll compare all three Kerastase Therapiste products to similar Olaplex products. Let’s look at the popular restorative hair care products from both brands and see how they measure up.
Olaplex vs Kerastase: Shampoo
Both Olaplex and Kerastase Resistance shampoos target damaged hair and repair and strengthen weak strands for healthier, silky soft hair.
Olaplex No. 4 Bond Maintenance Shampoo
Olaplex No. 4 Bond Maintenance Shampoo is a sulfate-free formula that cleanses and strengthens the hair.
This #1 selling Prestige Shampoo* is designed to be used as part of the multi-step Olaplex system but can also be used on its own with other haircare products.
Formulated for all hair types, Bond Maintenance Shampoo contains Olaplex’s patented bond-building technology.
The shampoo repairs and protects against damaged tresses, split ends, and frizz by re-linking the broken disulfide bonds in your hair.
The result is shinier, more manageable, stronger hair with reduced breakage.
This color-safe shampoo has a thick texture and Olaplex’s signature scent. It leaves hair feeling clean but not stripped, just silky and soft.
At the time of this writing, Olaplex offers two additional shampoos formulated with Olaplex’s bond-building technology, a clarifying shampoo, Nº.4C Bond Maintenance Clarifying Shampoo, and shampoo for blonde hair, Nº.4P Blonde Enhancer Toning Shampoo.
NOTE: Olaplex notes that it is a myth that their products are protein treatments. Although some of their products contain a minimal amount of protein, they don’t contain enough to be considered a protein treatment.
Protein treatments fill in the gaps of a weakened hair cuticle to protect it from environmental damage, but they don’t actually rebuild the hair.
Olaplex rebuilds the hair from the inside out by repairing the disulfide bonds that give hair its strength. As a result, hair is stronger and less likely to break and need protein treatments to begin with.
Kerastase Resistance Bain Therapiste Shampoo
Kerastase Resistance Bain Therapiste Shampoo repairs very damaged hair with a combination of key actives like a gluco peptide, a wheat protein derivative, and native plant cells.
Gluco-peptides penetrate deep into your hair cuticles. They help to fortify your hair for improved strength and fullness. A wheat protein derivative improves hair elasticity and flexibility for improved smoothness.
Salicylic acid works to exfoliate the scalp and remove buildup.
Kerastase’s unique blend of fortifying ingredients strengthens and restructures very damaged hair from the inside out for noticeably healthier hair that is less prone to breakage.
This shampoo has a creamy texture and a noticeable perfume-like scent. It leaves hair feeling clean and looking shiny and manageable.
Kerastase’s Bain Thérapiste Shampoo is ideal for those with very damaged hair that needs to be repaired and strengthened.
Which Shampoo Is Better?
Both Olaplex and Kerastase offer high-quality, effective shampoos for damaged hair. Both strengthen hair but go about it differently.
Olaplex rebuilds hair from the inside out by repairing disulfide bonds. Kerastase uses a combination of ingredients to fortify very damaged hair and improve elasticity, fullness, and smoothness.
So, which one is better? It depends on your hair needs:
If your hair is very damaged and deals with split ends and frizz, Olaplex might be the better option. Kerastase may be the better option if you’re looking to improve elasticity, smoothness, and scalp buildup.
Olexplex vs Kerastase: Conditioner
Now we get to the products that really help make damaged hair look better: conditioners!
Olaplex No. 5 Bond Maintenance Conditioner
Alongside best-selling Olaplex Bond Maintenance Shampoo, Olaplex No. 5 Bond Maintenance Conditioner is the #1 best-selling Prestige Conditioner.*
It is formulated to repair hair damage, split ends, and frizz, leaving your hair more manageable, shiny, and strong.
It re-links the broken disulfide bonds in every strand of your hair to repair damage from the inside out. The result is stronger, healthier, smoother hair that’s less likely to tangle or break.
It does a fantastic job of controlling frizz and adding shine, and it’s gentle enough to use on color-treated hair.
Apply this conditioner for 3 minutes and then rinse. It can be used daily.
*Per The NPD Group/U.S. Prestige Beauty Total Measured Market, Hair Sales, Annual 2021.
Kerastase Resistance Masque Therapiste Hair Mask
Since Kerastase does not offer a traditional conditioner in the Therapiste line, we’ll look at the benefits of the deep conditioner in this line: Therapiste Hair Mask.
Kerastase Resistance Masque Therapiste Hair Mask for damaged hair deeply nourishes very damaged hair and protects hair from breakage.
It uses the same active ingredients as the shampoo, including gluco peptides, a wheat protein derivative, and native plant cells to repair damage, deeply hydrate and reduce the chance of weakened roots.
The thick, repairing hair mask coats each strand from mid-length to end to deliver intense hydration and fortifying nutrients.
It leaves hair looking and feeling soft, smooth, and healthy, with less hair breakage.
While you should apply Olaplex conditioner for 3 minutes, this Kerastase hair treatment should be applied for 5-10 minutes. Like Olaplex, it can be used daily.
Which Conditioner Is Better?
Both deep conditioners repair damaged hair and leave your hair looking healthier. Olaplex is designed to repair damage from the inside out from a molecular level with its bond-building technology.
In contrast, Kerastase is designed to strengthen and repair very damaged hair, improve elasticity, and prevent future breakage.
Personally, I find that Olaplex works better on my frizz and leaves my hair smoother. Also, if you are in a rush, Olaplex is a quicker option.
If price is an issue, please note that this Kerastase hair mask is over twice the price of Olaplex conditioner.
Olaplex vs Kerastase: Hair Treatments
When discussing hair treatments between the two brands, it is important to note that when referencing Olaplex’s multi-step system, the first two treatment steps are salon treatments.
The next treatment step is Olaplex No. 3 Hair Perfector, which is Olaplex’s best-selling at-home hair treatment. Note that you don’t need to complete in-salon Steps 1 and 2 before using No. 3.
The in-salon treatments offered by Olaplex (Step 1 and Step 2) begin with Olaplex No.1 Bond Multiplier. This is used as an additive during chemical processing to reduce damage. It is also a stand-alone treatment to repair and prevent hair damage.
Olaplex No.2 Bond Perfector, Step 2 of the Olaplex system, is a stand-alone in-salon treatment that repairs bonds after chemical treatments.
Kerastase Fusio Dose is also an in-salon treatment, although you can purchase some Fusio Dose products online.
Let’s look at Olaplex No. 3 Hair Perfector compared to Kerastase Fusion Dose hair treatments:
Olaplex No. 3 Hair Perfector
Olaplex No. 3 Hair Perfector is so popular that it is the #1 selling product in Prestige Haircare.** It is a weekly at-home treatment formulated to reduce breakage and strengthen hair for healthier-looking hair.
Per Olaplex, one No. 3 is sold every 3.5 seconds!
Olaplex No.3 uses Olaplex’s bond-building technology to mend hair damaged by chemical treatments, heat styling, and everyday wear-and-tear.
It works great on all hair types and textures and is gentle enough to use on color-treated hair.
Olaplex No.3 is a pre-shampoo and conditioner treatment meant to be applied to damp hair for 10 minutes.
After rinsing, you can shampoo and condition your hair. It can be used once a week or as much as two to three times a week for damaged hair.
For best results, this step 3 Olaplex treatment can be paired with Olaplex No. 0 Intensive Bond Building Treatment, another at-home treatment formulated to prime hair for Olaplex No.3 Hair Perfector.
**Per The NPD Group/U.S. Prestige Beauty Total Measured Market, Haircare Product Sales from January-September 2021.
Kerastase Fusio Dose
Kerastase Fusio Dose is an in-salon customized hair treatment.
Your Kerastase stylist will evaluate your hair needs to create a fresh-mixed and custom-blended Concentré to address your main hair concern and a Booster designed to help you reach your hair goals.
The application takes only 5 minutes and replaces a conditioner or hair mask you would get in the salon. (Kerastase notes that Fusio-Dose molecules are up to 100x smaller than a traditional haircare product.)
There are 30 different combinations for a specialized Fusio Dose treatment, as there are 6 Concentrés & 5 Boosters of Fusio Dose.
Concentré options are:
- Concentré Blond Absolu (infused with hyaluronic acid violet direct dye)
- Concentré Nutritive (infused with niacinamide)
- Concentré Genesis (infused with collagen peptides)
- Concentré Resistance (infused with ceramides)
- Concentré Curl Manifesto (infused with glycerin)
- Concentré Chroma Absolu (infused with lactic acid and Centella Asiatica)
Booster options are:
- Booster Cicablond (infused with vitamin E)
- Booster Nutrition (infused with camellia oil)
- Booster Anti-Frizz (infused with polypeptides)
- Booster Brilliance (infused with lactic acid and tartaric acid)
Which Hair Treatment Is Better?
If you have the budget and access to a salon near you that offers Kerastase treatments, Fusio Dose could be an excellent way to get a customized hair treatment that addresses your specific hair concerns.
Otherwise, Olaplex No.3 will probably be your best bet. (I love how my hair looks and feels after using it.)
If you do choose to go with Fusio Dose, note that there are many different combinations of Fusion Dose Concentré and Boosters.
It is probably best to have the treatment done in a salon and work with professionals who can evaluate your hair instead of purchasing the products online.
If pricing is a concern, please note that Fusio Dose is much more expensive than Olaplex No.3.
Olaplex vs Kerastase: Hair Serum
Olaplex No. 9 Bond Protector Nourishing Hair Serum
Olaplex No. 9 Bond Protector Nourishing Hair Serum is a leave-in hair serum that protects your hair from daily damage from environmental effects like pollution and heat styling.
Along with Olaplex’s bond-building technology, this hair serum contains red algae extract, which contains antioxidants that help to protect the hair from oxidative stress.
The serum does a great job of tamping down frizzy hair, detangling, reducing static, and adding brilliant shine without being oily or creating stickiness.
The super lightweight silicone-free serum offers heat protection up to 450°F (232°C).
Kerastase Resistance Sérum Thérapiste Hair Serum
Kerastase Resistance Sérum Thérapiste Hair Serum is a repairing serum for weak, over-processed, and very damaged hair.
The serum uses Therapiste active ingredients like gluco peptides, a wheat protein derivative, and native plant cells to hydrate your hair and strengthen the cuticle to prevent hair damage before blow drying.
The serum has a unique pump that dispenses a cream from one chamber and serum from the other.
Mix the two together to get a lightweight serum that offers heat protection up to 450°F (232°C). The light creamy texture soothes itchy scalps.
The serum is safe for color-treated hair and works best on mid-lengths to ends on towel-dried hair. It can also be used as a finisher on dry hair to control flyaways and seal those annoying split ends.
Which Hair Serum Is Better?
Both serums target hair damage and provide heat protection up to 450°F (232°C) but use different ingredients to repair hair.
Olaplex uses Bis-Aminopropyl Diglycol Dimaleate to repair broken disulfide bonds, while Kerases uses gluco peptides, a wheat protein derivative, and hydrating native plant cells to restore hair.
Kerastase provides the benefits of both a cream and a serum in one with its dual chamber pump.
Olaplex comes in a 3 oz bottle, while Kerastase comes in a 1 oz bottle and is more expensive than Olaplex.
Both serums are very lightweight, but Olaplex feels a bit lighter in my hair. I reach for Olaplex more often to add shine and control flyaways.
Olaplex Bond-Building Hair Care Products vs Kerastase Resistance Therapiste Products
Olapelx and Kerastase offer high-quality products for damaged hair, but the brands strengthen hair in different ways.
Olaplex rebuilds hair from the inside out by repairing disulfide bonds, while Kerastase uses a combination of ingredients to fortify very damaged hair.
Olaplex has a wealth of information on its website about its formulas and ingredients. It was more challenging to determine the benefits of Kerastase products.
Unlike Olaplex, Kerastase is not cruelty-free. Olaplex is also a vegan hair care brand.
Olaplex vs Kerastase: Pricing
While neither brand offers drugstore pricing, Kerastase is a truly luxury haircare brand, and its prices reflect it.
Kerastase is much more expensive than Olaplex and may not be practical for some budgets.
Final Thoughts: Olaplex vs Kerastase
Both brands offer in-salon treatments and at-home treatments to help repair damaged hair.
I think both work well, but I had a better experience with Olaplex than Kerastase Therapiste, from the formulas and fragrances to the pricing and results.
Keep in mind that Kerastase Resistance Therapiste is just one of several lines that Kerastase offers.
Kerastase Bain Satin 2 Nutritive Shampoo has been one of my favorite shampoos for years, so if you are looking for a luxury smoothing shampoo for dry hair, it could be worth a try.
For another Kerastase comparison, please see my Oribe vs Kerastase post.
Thanks for reading!