Kerastase Genesis Serum Fortifiant — 3.04 oz container

Kerastase

Genesis Serum Fortifiant

Scalp treatment

Scalp treatment
Sulfate-free
Silicone-free
Protein-free
Not cruelty-free · PETA-listed

Size3.04 fl oz

Price$64seen at one store · 3.04 oz

Price / oz$21.05/ozat 3.04 oz

Where to buy2 stores · $52.00–64.00

Add it to your products. We’ll tell you if it’s ever recalled.

Scent:

The ingredient list declares fragrance. What it smells of is not stated, and we do not guess.

Listing used for research: lookfantastic.com

Personal fit

Is this right for you?

Factor Your profile Fit

Best for hair types All types Not in your profile

Moisture level Moderate Not in your profile

Slip / detangling Little Not in your profile

Weight on hair Light Not in your profile

Fragrance Present Not in your profile

Protein None Not in your profile

Silicone / wax buildup None Not in your profile

Clarifying wash needed Moderate Not in your profile

Parabens / preservatives None of these listed Not in your profile

Essential oils None listed Not in your profile

Show all 19 factors we check

The rest of what your plan weighs on this product.

Fast-drying alcohol High Not in your profile

Vegan / cruelty-free Not cruelty-free · PETA-listed Not in your profile

Animal-derived ingredients Not yet verified Not in your profile

Heavy humectants Not heavy Not in your profile

Hard-water defence None Not in your profile

UV filter None listed Not in your profile

Ingredient list 30 ingredientsAbout average Not in your profile

Price tier Prestige Not in your profile

Where to buy it Brand websiteOne channel Not in your profile

The consultation builds your hair profile, checks every factor in this table against it, and tells you where this product fits or what to use instead.

Start your consultation

$49 once, with 60 days of follow-up questions and plan updates. Nothing renews, and you never have to buy a product.

Same job for less elsewhere

$21.05/oz at 3.04 oz, more than 78% of the 280 scalp treatments , which mostly run $3.84–19.05/oz.

View alternatives

Great for

Flaking scalpsit has an over-the-counter active

Protein-sensitive hairthat stiffens when protein is added

Fine hairthat flattens under most products

Silicone-free routinesno silicones appear in the list

Maybe skip if

this product has a scent

Very dry or damaged hairit contains fast-drying alcohol

Non-medicated routinesthis is an over-the-counter drug as well as a cosmetic

Vegan and cruelty-freeour record does not support both claims here

Tight budgetsit sits in the upper price tiers

Picking it up locallywe’ve only seen it sold in one channel

Whether this much richness suits you depends on your strand thickness, porosity and how easily your hair goes flat. We work that out in the consultation.

What the formula actually does

Read from the label, not the marketing

Each row says where it comes from: F means we derived it from this product’s own ingredient list, S means it is a claim the brand makes that the formula neither confirms nor contradicts.

Slip and detangling Little

Nothing here is built to reduce combing force.

Oils and butters None

No oils or butters in the list.

Weight on the hair Light

Water-first and light: unlikely to flatten fine hair.

Water-binding (humectants) Moderate

Humectants in the working part of the formula.

Protein None

No protein or amino acids in the list.

Needs detergent to remove No

Nothing here needs a detergent wash to remove.

Hard-water defence None

No chelating agent in the list.

Fragrance Present

Fragrance is listed; it sits below the working ingredients.

from the formula stated by the brand reported by reviewers Scale: 1 dot low · 5 dots high, within this product type.

Ingredients that matter

The ingredients that change a decision

The workhorse ingredients, plus anything lower down that changes a decision. The chips name what an ingredient does. They are not safety scores, and no ingredient here is rated good or bad on its own.

Ingredient	What it does	Why it matters	Chip
WaterAqua/Water/Eau	solvent	The base everything else is dissolved in	Neutral
Alcohol Denat.Alcohol Denat	drying alcohol	Speeds drying but can leave hair feeling dry	Drying
AminexilDiaminopyrimidine Oxide	active	The over-the-counter active	Active
Ammonium Polyacryloyldimethyl Taurate	thickener	Sets the texture	Holds
Aminomethyl Propanol	pH adjuster	Fine-tunes the pH	pH balancer
Citric Acid	pH adjuster	Fine-tunes the pH	pH balancer
PEG-40 Hydrogenated Castor Oil	solubilizer	Helps dissolve the oils	Stabilizes
Piroctone Olamine	active	A secondary active	Active
Caffeine	active	A secondary active	Active
Limonene	fragrance	The scent	Fragrance
Linalool	fragrance	The scent	Fragrance
Benzyl Salicylate	fragrance	The scent	Fragrance

What the list leaves out, and what it carriesThe list carries no sulfates or silicones. No protein: a moisture formula, not a repair one. Fragrance is on the label. Carries an over-the-counter scalp active (piroctone olamine).

Full ingredient list (30)

In the US, ingredients above 1% are listed from most to least. Below 1% they can appear in any order. Each note keeps three things apart: what the ingredient generally does, its role in this type of product, and what its position can tell you.

1 Water · Aqua/Water/Eau

General function
The base of almost every rinse-off and cream hair product. It carries everything else and is normally the first ingredient on the label.

Leading ingredient
Listed in the first three ingredients, it is likely a structural part of this formula.
- solvent
2 Alcohol Denat. · Alcohol Denat

General function
Fast-drying alcohol used to make sprays set quickly. In leave-on products it can leave hair feeling dry, especially in high position on the list.

Leading ingredient
Listed in the first three ingredients, it is likely a structural part of this formula.

May suitFine or easily flattened hair
Evaporates on contact, which is how a spray sets almost instantly and leaves no weight behind it.

May not suitDry, coarse, or high-porosity hair
Porous hair gives water up easily as it is; a fast-evaporating solvent high on the list accelerates that.

May not suitVery dry or highly damaged hair
It evaporates quickly and takes some water with it. On hair already short of moisture, a formula built on a lot of it can finish drier than it started.

PubChem
- drying alcohol
- solvent
3 Aminexil · Diaminopyrimidine Oxide

General function
An ingredient sold under the trade name Aminexil that brands include in scalp tonics positioned for fuller-looking hair. It usually appears alongside other scalp-care ingredients in professional lines rather than on its own.

Leading ingredient
Listed in the first three ingredients, it is likely a structural part of this formula.
- active
4 Ammonium Polyacryloyldimethyl Taurate

General function
A synthetic thickener that gels water quickly and holds oils in suspension. It gives creams a light, springy texture.

Supporting ingredient
Listed in positions 4–8, it likely makes a meaningful contribution alongside the formula's main ingredients.
- thickener
- polymer
▾Below about here, the order stops meaning much. These are usually used at 1% or less.
5 Aminomethyl Propanol

General function
A base used in trace amounts to neutralise acidic hold polymers so they thicken and set properly.

Estimated lower-concentration zone
It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

DependsFrizz-prone, damaged, or high-friction hair
pH adjusters are how a formula is brought to a chosen acidity, and an acidic formula keeps the cuticle lying flatter than an alkaline one. Which way this one moves the pH depends on the formula, and the finished pH is not on the label.

PubChem
- pH adjuster
6 Citric Acid

General function
Used to bring the product to a slightly acidic pH, which helps the cuticle lie flat. It is almost always near the end of the list.

Estimated lower-concentration zone
It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

May suitBuild-up-sensitive routines
Holds hard-water minerals in solution so they rinse away instead of depositing on the hair.

May suitFrizz-prone, damaged, or high-friction hair
The acid side of pH adjustment, and the reason it matters is measured: alkaline formulas raise the fibre's surface negative charge, increase friction between strands and lift the scales, while lower-pH ones do the reverse.

May suitGray, silver, or brass-prone hair
Where a warm cast comes from water minerals rather than from the hair itself, holding those metals in solution is what removes it.

International Journal of Trichology
- pH adjuster
- hard-water chelator
7 PEG-40 Hydrogenated Castor Oil

General function
A castor-oil derivative that dissolves fragrance and oils into water so the product stays clear and does not separate.

Estimated lower-concentration zone
It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
- solubilizer
- emulsifier
8 Piroctone Olamine

General function
An anti-flaking agent common outside the United States, used at cosmetic levels here.

Estimated lower-concentration zone
It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.
PubChem
- active
9 Caffeine
- active
10 Arginine

General function
An amino acid that holds water and carries a positive charge, so it is drawn to damaged spots on the strand.

Estimated lower-concentration zone
It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

May suitVery dry or highly damaged hair
Amino acids are the smallest protein fraction and bind water as well, so they add far less stiffness than a hydrolysed protein does.

DependsClimate-sensitive or frizz-prone hair
A humectant follows the air: it holds water in humid conditions and can give it up in very dry ones. Climate decides what it does more than the label does.

DependsProtein-sensitive hair
The lightest option in the protein family, but still protein — worth watching if protein reliably stiffens your hair.

PubChem
- amino acid
- humectant
11 Limonene

General function
A citrus-smelling fragrance component that EU rules require to be named separately because some people react to it.

Estimated lower-concentration zone
It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

May not suitFragrance-sensitive routines
One of the 26 scent components the EU requires to be named individually above a threshold. It is named because it is a known contact allergen, not because it is unusual.

PubChem
- fragrance
- named fragrance allergen
12 Niacinamide

General function
Vitamin B3, used in scalp products for conditioning claims.

Estimated lower-concentration zone
It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

May suitFrizz-prone, damaged, or high-friction hair
Deposits a lubricating layer that makes combing easier, which is most of what stops mechanical damage adding to frizz.

PubChem
- vitamin
- conditioning agent
13 Pyridoxine Hcl
- vitamin
14 Linalool

General function
A floral fragrance component listed separately as a recognised contact allergen.

Estimated lower-concentration zone
It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

May not suitFragrance-sensitive routines
One of the 26 scent components the EU requires to be named individually above a threshold. It is named because it is a known contact allergen, not because it is unusual.

PubChem
- fragrance
- named fragrance allergen
15 Safflower Glucoside
- nonionic cleanser
- cleanser
16 Benzyl Salicylate

General function
A soft floral fragrance component listed separately as a recognised allergen.

Estimated lower-concentration zone
It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

May not suitFragrance-sensitive routines
One of the 26 scent components the EU requires to be named individually above a threshold. It is named because it is a known contact allergen, not because it is unusual.

PubChem
- fragrance
- named fragrance allergen
17 Coumarin

General function
A sweet, hay-like fragrance component listed separately as a recognised allergen.

Estimated lower-concentration zone
It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

May not suitFragrance-sensitive routines
One of the 26 scent components the EU requires to be named individually above a threshold. It is named because it is a known contact allergen, not because it is unusual.

PubChem
- fragrance
- named fragrance allergen
18 Citral

General function
A lemon-scented fragrance component listed separately as a recognised allergen.

Estimated lower-concentration zone
It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

May not suitFragrance-sensitive routines
One of the 26 scent components the EU requires to be named individually above a threshold. It is named because it is a known contact allergen, not because it is unusual.

PubChem
- fragrance
- named fragrance allergen
19 Benzyl Alcohol
- preservative
- solvent
20 Xylitylglucoside

General function
A sugar-derived humectant used for lasting moisture without stickiness.

Estimated lower-concentration zone
It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

May suitDry, coarse, or high-porosity hair
High-porosity hair loses water fast; a humectant holds some of it in place for longer than the wash itself would.

May suitVery dry or highly damaged hair
Binds water into the outer layers of the strand, and water is what makes dry hair flexible again rather than brittle.

DependsClimate-sensitive or frizz-prone hair
A humectant moves water in whichever direction the air allows: it holds moisture in humid conditions and can pull it back out of hair in very dry ones.

PubChem
- humectant
21 Citronellol

General function
A rose-like fragrance component named separately as a recognised allergen.

Estimated lower-concentration zone
It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

May not suitFragrance-sensitive routines
One of the 26 scent components the EU requires to be named individually above a threshold. It is named because it is a known contact allergen, not because it is unusual.

PubChem
- fragrance
- named fragrance allergen
22 Benzyl Benzoate

General function
A fragrance component with a faint balsamic scent, named separately on the label because it is a recognised contact allergen.

Estimated lower-concentration zone
It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

May not suitFragrance-sensitive routines
One of the 26 scent components the EU requires to be named individually above a threshold. It is named because it is a known contact allergen, not because it is unusual.

PubChem
- fragrance
- named fragrance allergen
23 Anhydroxylitol

General function
A sugar-derived humectant used with xylitol for a light moisturised feel.

Estimated lower-concentration zone
It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

May suitDry, coarse, or high-porosity hair
High-porosity hair loses water fast; a humectant holds some of it in place for longer than the wash itself would.

May suitVery dry or highly damaged hair
Binds water into the outer layers of the strand, and water is what makes dry hair flexible again rather than brittle.

DependsClimate-sensitive or frizz-prone hair
A humectant moves water in whichever direction the air allows: it holds moisture in humid conditions and can pull it back out of hair in very dry ones.

PubChem
- humectant
24 Xylitol

General function
A sugar alcohol that binds water and gives a light, non-sticky moisturised feel.

Estimated lower-concentration zone
It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

May suitDry, coarse, or high-porosity hair
High-porosity hair loses water fast; a humectant holds some of it in place for longer than the wash itself would.

May suitVery dry or highly damaged hair
Binds water into the outer layers of the strand, and water is what makes dry hair flexible again rather than brittle.

DependsClimate-sensitive or frizz-prone hair
A humectant moves water in whichever direction the air allows: it holds moisture in humid conditions and can pull it back out of hair in very dry ones.

PubChem
- humectant
25 Zingiber Officinale Root Extract/Ginger Root Extract
- botanical extract
26 Resveratrol
27 Tocopherol
- antioxidant
- vitamin
28 BHT
- antioxidant
29 Sodium Citrate

General function
Used with citric acid to hold the formula at a steady, slightly acidic pH. It also binds a little hard-water mineral.

Estimated lower-concentration zone
It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

May suitBuild-up-sensitive routines
Binds the calcium and magnesium in hard water, which is what stops mineral deposits accumulating on the strand wash after wash.

May suitGray, silver, or brass-prone hair
Copper and iron carried in tap water deposit on the strand and read as a dull, warm cast on gray or light hair. A chelator holds those metals in solution so the wash carries them off.

DependsFrizz-prone, damaged, or high-friction hair
pH adjusters are how a formula is brought to a chosen acidity, and an acidic formula keeps the cuticle lying flatter than an alkaline one. Which way this one moves the pH depends on the formula, and the finished pH is not on the label.

PubChem
- pH adjuster
- hard-water chelator
30 Fragrance · Parfum/Fragrance

General function
An undisclosed blend of scent ingredients. Regulations let it stay unlisted, so a fragrance-free product is the only way to be certain what is not in it.

Estimated lower-concentration zone
It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

May not suitFragrance-sensitive routines
Declared fragrance. On a fragrance-sensitive routine this is the line that decides it, wherever it sits on the label.
- fragrance
- declared fragrance

What the whole list adds up to

8 fragrances
7 named fragrance allergens
4 humectants
3 solvents
3 actives
3 pH adjusters
3 vitamins
2 hard-water chelators
2 antioxidants
1 drying alcohol
1 thickener
1 polymer
1 solubilizer
1 emulsifier

Ingredient list captured 2026-09-17. Formulas change, so check the package in your hand when an ingredient matters to you.

Price · 3.04 oz

Seen at $64 1 store · checked Sep 17

Good value under $23 Under $7.50/oz it costs less than three-quarters of the 8 products we score as doing the same job

Priced above the products that do the same job. Stores sell it above the $23 line; products that do this job typically go for about $44 at this size.

Show the price ladder

Price for 3.04 ozlower is better

Where we’ve seen it2 listings · 2 stores

LookFantastic
$52.00

3.04 oz · $17.11/oz

Sep 4Lowest per oz
blissbloombychristine.co
$64.00

3.04 oz · $21.05/oz

Sep 17

Sorted by price per ounce. Dated observations from our research, not live prices. Direct store pages, no affiliate links. We don’t sell this product.

How we work this out

3.04 oz is the size stores list most often; every comparison on this page is made at it. Other sizes are shown in the Sizes row and the store list.
Seen at $64 is the price we have observed for the 3.04 oz. We need three stores before we call a price commonly seen.
Good value under $23 comes from the 8 products we score as doing the same job as this one. A quarter of them cost less than $7.50/oz; at 3.04 oz that is $23. Under that line you are paying less than most of them.
About $44 is what those same products typically cost at this size: the midpoint of their prices per ounce, scaled to 3.04 oz.

Formula

Formula score

3 of 10

Above the range for scalp treatments per ounce for a shorter formula with no conditioning agents up front, and 4 close matches cost less.

How the score is counted

4 products that do the same job cost less per ounce
Costs more per ounce than 78% of the 280 scalp treatments we’ve priced
No conditioning agents up front in the formula
No oils or butters in the working zone either

Conditioning agents up frontWhat makes wet hair comb through.3 pts
Oils or butters in the working zoneSoftens the strand rather than just coating it.2 pts
Slip for detanglingReduces the force it takes to comb wet hair.2 pts
A humectantBinds water into the hair.1 pt
A pH adjusterBrings the formula to the acidic pH hair prefers.1 pt
Fragrance kept out of the top eightScent as a finishing touch, not a major share.1 pt

The formula score measures completeness for the job: a weighted share of the systems this product type is usually built around that we find in this list. It does not rate how well the product works or its quality, and it never compares across product types.

Does the same job, for less

Formulas that do the same things (cleanse, condition, coat or hold) for less per ounce. Scent, texture and where you buy them can still differ.

PhytoClosest function PHYTOLIUM+ Initial Stages Strengthening Treatment $8.17/oz $12.88/oz less

Lightweight
Silicone-free

Function: Protein
Also: Salon tier
3.4 oz bottle

Compare

As I AmLowest cost per oz Dry & Itchy Scalp Care Itch Soothing Drops $5.50/oz $15.55/oz less

Scalp active
Fragrance-free
Unscented

· Close function

Function: Water-binding (humectants)
Also: Unscented
Cruelty-free
Drugstore tier

Compare

KloraneClose function Intense Strengthening Serum with Quinine $10.15/oz $10.90/oz less

Protein-free
Lightweight
Silicone-free

Function: Water-binding (humectants)
Also: Salon tier
3.3 oz bottle

Compare

See more alternatives in the product library

These products do a similar job. We haven’t matched them to you. Find the one that fits your hair, routine and budget

Final decision

Should you buy it?

Hard to justify at this price

Best user

Flaking scalps, for an over-the-counter scalp active and a protein-free formula

Biggest tradeoff

Less suited to anyone sensitive to fragrance, very dry or high-damage hair, or anyone who does not want a medicated product

Best alternative if not

Phyto PHYTOLIUM+ Initial Stages Strengthening Treatment, for similar results at a lower price

We do not sell products or take placement fees. This page states what the formula and the prices show; the consultation is what matches it to a person.

Claims check

What the brand says, and what the formula shows

Claims are quoted from the brand. We mark a claim supported, partly supported or conflicting only when the ingredient list speaks to it. Everything else stays "stated by the brand". That isn’t a criticism: most claims can’t be checked from a label.

SupportedBacked by ingredients

Partly supportedSome supporting logic

Stated by brandNo clear evidence

Potential conflictFormula works against claim

anti hair-fall fortifying serum

No protein or bond ingredient appears in the list.

Arginine

Stated by brand

Can’t be confirmed from label.

improves scalp micro-circulation

This is a marketing claim; an ingredient list cannot speak to it.

—

Stated by brand

Can’t be confirmed from label.

helps anchor hair to the scalp

This is a marketing claim; an ingredient list cannot speak to it.

—

Stated by brand

Can’t be confirmed from label.

How to read this

We look at the first 10–15 ingredients and what they do in a formula, not at the marketing. If the list doesn't speak to a claim, we don't assume.

Reviewers

What people report

Themes that come up again and again in sourced reviews, written by our researchers in their own words. We don’t store or scrape star ratings.

Multiple reviewers describe inconsistent consistency between bottles (a thicker gel versus a watery liquid), raising formulation or authenticity concerns.

Most reviewers report noticeably reduced hair shedding and stronger-feeling hair after weeks of nightly or post-wash use.

The lightweight, fast-absorbing texture and pleasant scent are repeatedly praised as not leaving hair greasy, even on fine hair.

Some reviewers report scalp itching, tingling or an allergic-type reaction after starting regular use.

A significant number of US reviewers say the American formula lacks the Aminexil found in the Canadian/European version and feels like 'just water' with no hair-loss benefit.

How this page was made

Everything above comes from our researched product record: identity, the ingredient list as printed, the brand's own claims, dated prices and review themes our researchers wrote in their own words. No part of this page is written by hand for one product.
The value band is a fixed label over two stored numbers: this product’s cost per ounce as a percentile of every product of this type we have priced, each at the size it is most often sold in, and how many products we score as doing the same job cost at least a quarter less per ounce.
Both scores out of ten are defined on this page. The formula score is completeness for the job, computed from a fixed per-format checklist shown beneath the gauge; the price score is cost per ounce against every product of this type we have priced.
The "Is this right for you?" panel reads only your own consultation answers, and it applies exactly the filters our recommendation engine applies. It is computed when you load the page and is never stored on it.
5 sources consulted for this product (1 manufacturer or regulatory, 1 retailer, 3 editorial), last checked 2026-09-17.
Ingredient references are linked for 16 of 17 product-aware annotations on this page. Fit notes are general formulation guidance. They aren’t a verdict on the finished product or on you.
We haven’t tested this product in a lab, and we don’t physically test your hair. Formula readings come from the ingredient list. Claims about how it behaves are labelled as the brand's.
Ingredient order tells you relative amount only above roughly 1%. Prices are what we saw on the dates shown and can change.
Ingredient names link to our ingredient library, where each entry shows what it does, which product types use it, and where it usually sits on a label across everything we have researched.
This is cosmetic information, not medical advice, and nothing here diagnoses or treats a health condition.
Formula readings: derivation v23. Record last updated 2026-09-17.

Genesis Serum Fortifiant

Is this right for you?

Read from the label, not the marketing

The ingredients that change a decision

What the whole list adds up to

Should you buy it?

What the brand says, and what the formula shows

What people report

More from Kerastase

How this page was made

Hair Care Consultation