Here's our complete breakdown comparing the ingredients, attributes, and more of Olaplex No.4 Bond Maintenance Shampoo versus K18 Hair PEPTIDE PREP™ pH Maintenance Shampoo .
Published on March 15, 2023
Overview
What they are
These products are both vegan, cruelty-free, and reef safe shampoos. They have a total of 8 ingredients in common
Suited For
They're both likely to be good for dry skin, brightening skin and sensitive skin
Free From
They both do not contain any harsh alcohols, parabens or sulfates
What's Inside
They both contain fragrances
We independently verify ingredients, and our claims are backed by peer-reviewed research. Spot a product that need an update? Let us know.
Price
Ingredient Info
Olaplex No.4 Bond Maintenance Shampoo 63 ingredients
K18 Hair PEPTIDE PREP™ pH Maintenance Shampoo 18 ingredients
Alcohol Free
This product is free of harsh alcohols 🎉
Contains Silicon
Ingredients in this product that are types of silicon:
Contains Fragrance
Ingredients in this product that are forms of fragrance:
Sulfate Free
This product is free of sulfates 🎉
Paraben Free
This product is free of parabens 🎉
Contains Oils
Ingredients in this product that are types of oil:
Not Malassezia Safe
Ingredients in this product that are not malassezia safe:
Reef Safe
This product is free of ingredients that damage reefs 🎉
Contains EU Allergens
Ingredients in this product that are EU allergens:
Vegan
This product is vegan 🎉
Cruelty Free
This product is cruelty-free 🎉
Alcohol Free
This product is free of harsh alcohols 🎉
Silicon Free
This product is free of silicons 🎉
Sulfate Free
This product is free of sulfates 🎉
Paraben Free
This product is free of parabens 🎉
Oil Free
This product is free of oils 🎉
Malassezia Safe
This product is free of malassezia feeding ingredients 🎉
Reef Safe
This product is free of ingredients that damage reefs 🎉
EU Allergen Free
This product is free of EU allergens 🎉
Vegan
This product is vegan 🎉
Cruelty Free
This product is cruelty-free 🎉
At a glance
Click on any of the items below to learn more
Olaplex No.4 Bond Maintenance Shampoo 63 ingredients
K18 Hair PEPTIDE PREP™ pH Maintenance Shampoo 18 ingredients
Notable Ingredients
This product contains 1 ingredient that may have this attribute:
This product contains 1 ingredient that may have this attribute:
This product contains 1 ingredient that may have this attribute:
Benefits
This product contains 4 ingredients that may have this attribute:
This product contains 1 ingredient that may have this attribute:
This product contains 1 ingredient that may have this attribute:
This product contains 1 ingredient that may have this attribute:
This product contains 2 ingredients that may have this attribute:
This product contains 1 ingredient that may have this attribute:
This product contains 2 ingredients that may have this attribute:
This product contains 3 ingredients that may have this attribute:
Concerns
This product contains 1 ingredient that may have this attribute:
This product contains 1 ingredient that may have this attribute:
This product contains 2 ingredients that may have this attribute:
This product contains 2 ingredients that may have this attribute:
This product contains 1 ingredient that may have this attribute:
Benefits
This product contains 1 ingredient that may have this attribute:
This product contains 1 ingredient that may have this attribute:
This product contains 1 ingredient that may have this attribute:
Concerns
This product contains 1 ingredient that may have this attribute:
This product contains 1 ingredient that may have this attribute:
This product contains 3 ingredients that may have this attribute:
Build your routine, track which ingredients work for you, and much more with your free account.
Join SkinSortIngredients Compared
Ingredients that are highlighted in purple are present in both products.
Olaplex No.4 Bond Maintenance Shampoo 63 ingredients
K18 Hair PEPTIDE PREP™ pH Maintenance Shampoo 18 ingredients
Water • Sodium Lauroyl Methyl Isethionate • Cocamidopropyl Hydroxysultaine • Potassium Cocoyl Glycinate • Disodium Cocoyl Glutamate • Potassium Cocoate • Sodium Lauroyl Sarcosinate • Glycereth-26 • Decyl Glucoside • Parfum • Phenoxyethanol • Cocamidopropylamine Oxide • Sodium Cocoyl Glutamate • Glycol Distearate • Disodium Laureth Sulfosuccinate • Methyl Gluceth-20 • Acrylates Copolymer • Peg-120 Methyl Glucose Dioleate • Amodimethicone • Polyquaternium-10 • Citric Acid • Ethylhexylglycerin • Sodium Lauryl Sulfoacetate • Divinyldimethicone/Dimethicone Copolymer • Chlorphenesin • Polyquaternium-11 • Guar Hydroxypropyltrimonium Chloride • C11-15 Pareth-7 • Trisodium Ethylenediamine Disuccinate • Laureth-9 • Glycerin • Trideceth-12 • Panthenol • Hydrolyzed Vegetable Protein Pg-Propyl Silanetriol • C12-13 Pareth-3 • C12-13 Pareth-23 • Helianthus Annuus Seed Oil • Tocopherol • Pseudozyma Epicola/Camellia Sinensis Seed Oil Ferment Extract Filtrate • Argania Spinosa Kernel Oil • Rice Ferment Filtrate • Prunus Armeniaca Kernel Oil • Quaternium-95 • Propanediol • Helianthus Annuus Seed Extract • Peg-8 • Bis-Aminopropyl Diglycol Dimaleate • Euterpe Oleracea Fruit Extract • Rosmarinus Officinalis Leaf Extract • Punica Granatum Extract • Origanum Vulgare Leaf Extract • Musa Sapientum Fruit Extract • Morinda Citrifolia Fruit Extract • Sodium Hyaluronate • Peg-8/Smdi Copolymer • Arctium Lappa Root Extract • Sodium Polyacrylate • Palmitoyl Myristyl Serinate • Citral • Hexyl Cinnamal • Limonene • Biotin • Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate
Water • Sodium C14-16 Olefin Sulfonate • Cocamidopropyl Betaine • Sodium Methyl 2-Sulfolaurate • Sodium Lauryl Sulfoacetate • Sh-Oligopeptide-78 • Panthenol • Glycerin • Sodium Phytate • Guar Hydroxypropyltrimonium Chloride • Disodium 2-Sulfolaurate • Caprylyl Glycol • Caprylhydroxamic Acid • Benzoic Acid • Citric Acid • Sodium Hydroxide • Parfum • Limonene
Ingredients Side-by-side
Ingredients that are highlighted in purple are present in both products.
Learn more about what what Com. / Irr. ratings are
Ingredients Explained
These ingredients are found in both products.
Ingredients higher up in an ingredient list are typically present in a larger amount.
Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.
So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.
You'll also recognize water as that liquid we all need to stay alive. Talk about multi-purpose! If you see this, drink a glass of water. Stay hydrated!
Learn more about WaterOlaplex No.4 Bond Maintenance Shampoo contains this as ingredient number 1.
K18 Hair PEPTIDE PREP™ pH Maintenance Shampoo contains this as ingredient number 1.
Parfum is a catch-all term for an ingredient or more that is used to give aroma to products. Parfum, or fragrance, can be a blend of hundreds of chemicals or plant oils. This means every product with "fragrance" or "Parfum" in the ingredients list is a different mixture.
In the US, the alternative name for parfum is 'fragrance'. The term 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term.
For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance. One example is Calendula flower extract. Essential oil ingredients still impart a scent or 'fragrance'.
Depending on the blend, it can cause allergies and sensitivities on the skin. Some ingredients that are known EU allergens include linalool and citronellol.
Products use parfum often to give products a scent or cover up smells of different ingredients.
The bottom line is: not all fragrances/parfum/ingredients are created equally. If you are worried about fragrances, we recommend taking a closer look at an ingredient. And of course, we always recommend speaking with a professional.
Learn more about ParfumOlaplex No.4 Bond Maintenance Shampoo contains this as ingredient number 10.
K18 Hair PEPTIDE PREP™ pH Maintenance Shampoo contains this as ingredient number 17.
Citric Acid is an AHA derived from citrus fruits (think oranges, lemons, and limes!).
If you spot Citric Acid near the end of an ingredient list, it's likely there as a pH adjuster rather than an active ingredient.
As an AHA, Citric Acid removes the top layer of skin cells from the newer layer of skin underneath. This helps skin to remove dark spots and look more even.
Read more about some other popular AHA's here:
Learn more about Citric AcidOlaplex No.4 Bond Maintenance Shampoo contains this as ingredient number 21.
K18 Hair PEPTIDE PREP™ pH Maintenance Shampoo contains this as ingredient number 15.
Sodium Lauryl Sulfoacetate is an organic salt with a naturally sweet odor.
In cosmetics, this ingredient is used to increase the volume of foam. It is also an emulsifier and cleansing agent.
Sodium Lauryl Sulfoacetate helps reduce the surface tension of dirt, oil, and other pollutants.
Cosmetic Ingredient Review found this ingredient to irritate the eyes and skin in concentrations of 0.18% and 0.7%.
Learn more about Sodium Lauryl SulfoacetateOlaplex No.4 Bond Maintenance Shampoo contains this as ingredient number 23.
K18 Hair PEPTIDE PREP™ pH Maintenance Shampoo contains this as ingredient number 5.
This ingredient is derived from guar gum.
It is a conditioning ingredient, meaning it helps soften skin and hair.
Olaplex No.4 Bond Maintenance Shampoo contains this as ingredient number 27.
K18 Hair PEPTIDE PREP™ pH Maintenance Shampoo contains this as ingredient number 10.
Glycerin is already naturally found in your skin. It helps moisturize and protect your skin.
A study from 2016 found glycerin to be more effective as a humectant than AHAs and hyaluronic acid.
As a humectant, it helps the skin stay hydrated by pulling moisture to your skin. The low molecular weight of glycerin allows it to pull moisture into the deeper layers of your skin.
Hydrated skin improves your skin barrier; Your skin barrier helps protect against irritants and bacteria.
Glycerin has also been found to have antimicrobial and antiviral properties. Due to these properties, glycerin is often used in wound and burn treatments.
In cosmetics, glycerin is usually derived from plants such as soybean or palm. However, it can also be sourced from animals, such as tallow or animal fat.
This ingredient is organic, colorless, odorless, and non-toxic.
Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
Learn more about GlycerinOlaplex No.4 Bond Maintenance Shampoo contains this as ingredient number 31.
K18 Hair PEPTIDE PREP™ pH Maintenance Shampoo contains this as ingredient number 8.
Panthenol (also referred to as pro-vitamin B5) is a common ingredient that helps hydrate and soothe the skin.
lt is a humectant, meaning that it helps the skin attract and retain moisture.
Another benefit is the anti-inflammatory abilities. This means that it's great for sensitive, irritation-prone skin.
Once oxidized, panthenol converts to pantothenic acid. Panthothenic acid is found in all living cells.
Learn more about PanthenolOlaplex No.4 Bond Maintenance Shampoo contains this as ingredient number 33.
K18 Hair PEPTIDE PREP™ pH Maintenance Shampoo contains this as ingredient number 7.
Limonene is a fragrance that adds scent and taste to a formulation.
It's found in the peel oil of citrus fruits and other plants such as lavender and eucalyptus. The scent of limonene is generally described as "sweet citrus".
Limonene acts as an antioxidant, meaning it helps neutralize free radicals.
When exposed to air, oxidized limonene may sensitize the skin. Because of this, limonene is often avoided by people with sensitive skin.
The term 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term. For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance.
Learn more about LimoneneOlaplex No.4 Bond Maintenance Shampoo contains this as ingredient number 61.
K18 Hair PEPTIDE PREP™ pH Maintenance Shampoo contains this as ingredient number 18.
Here's what our community thinks of the ingredients in these two products.
Olaplex No.4 Bond Maintenance Shampoo 63 ingredients
K18 Hair PEPTIDE PREP™ pH Maintenance Shampoo 18 ingredients
Usage
Here's some more info on how this product is used by our community.
When to use
Olaplex No.4 Bond Maintenance Shampoo 63 ingredients
K18 Hair PEPTIDE PREP™ pH Maintenance Shampoo 18 ingredients
Reviews
Here's what our community thinks
Olaplex No.4 Bond Maintenance Shampoo 63 ingredients
BubbIes
You honestly shouldn’t be using this unless you have color treated hair, which is something I realized after using this for awhile. This is very...
You honestly shouldn’t be using this unless you have color treated hair, which is something I realized after using this for awhile. This is very heavy, I found that it weighed my hair down and made it look lifeless.
K18 Hair PEPTIDE PREP™ pH Maintenance Shampoo 18 ingredients
Alternatives
Our Dupe Finder has found 41 potential alternatives that have similar ingredients to Olaplex No.4 Bond Maintenance Shampoo.
See 41 alternativesOur Dupe Finder has found 50 potential alternatives that have similar ingredients to K18 Hair PEPTIDE PREP™ pH Maintenance Shampoo.
See 50 alternatives
