Act+Acre Daily Hydro Scalp Serum with Hyaluronic Acid — 1 oz container

Act+Acre

Daily Hydro Scalp Serum with Hyaluronic Acid

Scalp treatment

Scalp treatment
serum
Sulfate-free
Silicone-free

Size1 fl oz

Priceabout $24commonly seen · 1 oz

Price / oz$24.00/ozat 1 oz

Where to buy4 stores · $24.00–24.00

Manufacturer page: actandacre.com

Personal fit

Is this right for you?

Factor Your profile Fit

Best for hair types All types Not in your profile

Moisture level High Not in your profile

Slip / detangling Little Not in your profile

Weight on hair Light Not in your profile

Fragrance None listed 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 None Not in your profile

Vegan / cruelty-free Not yet verified Not in your profile

Animal-derived ingredients Not yet verified Not in your profile

Heavy humectants Heavy Not in your profile

Hard-water defence High Not in your profile

UV filter None listed Not in your profile

Ingredient list 23 ingredientsAbout average Not in your profile

Price tier Masstige Not in your profile

Where to buy it Brand website · Specialty beauty Not in your profile

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

Start your consultation

$49.00 once, for your consultation and hair profile. No subscription, no required purchases.

Same job for less elsewhere

$24.00/oz at 1 oz — more than 81% of the 152 scalp treatments , which mostly run $3.22–20.64/oz.

View alternatives

Great for

no fragrance (parfum) on the label

Protein-sensitive hairthat stiffens when protein is added

Fine hairthat flattens under most products

Silicone-free routinesno silicones appear in the list

Very dry hairno fast-drying alcohol in the list

Maybe skip if

Dry or very humid airwhere heavy humectants work against you

Whether this much richness is right for you depends on your strand thickness, porosity, and how easily your hair flattens — that is what the consultation works out.

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) High

Humectants near the top — water-binding is a headline mechanism here.

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 Chelators present

Chelators are present — they bind hard-water and pool minerals.

Fragrance None listed

No fragrance is listed.

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. These 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
Pentylene Glycol	humectant	Pulls water into the hair	Moisturizes
Propanediol	humectant	Pulls water into the hair	Moisturizes
Glycerin	humectant	Pulls water into the hair	Moisturizes
Sodium PCA	humectant	Pulls water into the hair	Moisturizes
Sodium Lactate	humectant	Adds a little water-binding	Moisturizes
Arginine	amino acid	A trace of amino acids	Protein
Sodium Hyaluronate	humectant	Adds a little water-binding	Moisturizes

What the list leaves out, and what it carriesThe list carries no sulfates, silicones, or drying alcohols. No protein — a moisture formula, not a repair one. Hard-water chelators are present.

Full ingredient list (23)

US labelling rules put ingredients above 1% in descending order of amount; below 1% they may be listed in any order. Annotations keep three readings separate: the ingredient's general function, its role in this product type, and what its position can support.

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 Pentylene Glycol

General function
A humectant that also helps preserve the formula, often used where a brand wants a short preservative list.

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

May suitFine or easily flattened hair
Light and water-binding rather than oily, so it hydrates without contributing weight.

May suitVery dry or highly damaged hair
A small water-binding solvent. It holds moisture and helps the rest of the formula spread evenly over the strand.

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.

PubChem
- humectant
- solvent
- preservative
3 Propanediol

General function
A corn-derived humectant and solvent, often chosen as a lighter-feeling alternative to propylene glycol.

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

May suitFine or easily flattened hair
Light and water-binding rather than oily, so it hydrates without contributing weight.

May suitVery dry or highly damaged hair
A small water-binding solvent. It holds moisture and helps the rest of the formula spread evenly over the strand.

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.

PubChem
- humectant
- solvent
4 Glycerin

General function
A small water-loving molecule that draws moisture into the hair and holds it there. It is the most common softening ingredient in conditioners and leave-ins.

Supporting ingredient
Listed in positions 4–8, it likely makes a meaningful contribution alongside the formula's main ingredients.

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
Water moves both ways. Measured across concentrations, glycerin solutions give water up in some conditions and take it from the air in others. What it does for you depends on how much of it is there and on the air around it.

Scientific Reports
- humectant
5 Sodium PCA

General function
A moisture-binding ingredient that occurs naturally in hair and skin.

Supporting ingredient
Listed in positions 4–8, it likely makes a meaningful contribution alongside the formula's main ingredients.

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
▾Below about this point, order stops being meaningful — these are typically used at 1% or less.
6 Sodium Lactate

General function
A salt of lactic acid used to hold moisture and steady the pH.

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.
- humectant
- pH adjuster
7 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
8 Sodium Hyaluronate

General function
A large water-binding molecule that sits on the surface holding moisture.

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.
- humectant
9 Sodium Gluconate

General function
A gentle, biodegradable chelator that binds hard-water minerals in place of EDTA.

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.

PubChem
- hard-water chelator
10 Aspartic Acid

General function
An amino acid used for moisture binding and to help set an acidic pH.

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.

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.

DependsProtein-sensitive hair
The lightest option in the protein family, but still protein — worth watching if protein reliably stiffens your hair.
- amino acid
- pH adjuster
11 Sodium PCA · PCA

General function
A moisture-binding ingredient that occurs naturally in hair and skin.

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
12 Caprylhydroxamic Acid

General function
A coconut-derived preservative booster that also binds trace metals.

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.

PubChem
- preservative
- hard-water chelator
13 Sodium Hyaluronate · Hyaluronic Acid

General function
A large water-binding molecule that sits on the surface holding moisture.

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.
- humectant
14 Sodium Anisate
15 Glycine

General function
The smallest amino acid in hair protein, added for moisture binding.

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.

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

PubChem
- amino acid
16 Alanine

General function
An amino acid found in hair protein, used in blends for moisture binding.

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.

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

General function
One of the amino acids that make up hair protein, added for water binding.

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.

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

General function
An amino acid used in hair conditioning blends.

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.

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

General function
An amino acid from hair protein, used in amino-acid conditioning blends.

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.

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

General function
An amino acid used in conditioning blends for moisture binding.

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.

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

General function
An amino acid used in conditioning blends that mimic hair's own protein.

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.

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

General function
One of the amino acids that make up hair protein, added for moisture binding.

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.

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

PubChem
- amino acid
23 Phenylalanine

General function
An amino acid found in hair protein, used in conditioning blends.

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.

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

What the whole list adds up to

11 amino acids
9 humectants
3 solvents
2 preservatives
2 pH adjusters
2 hard-water chelators

Drug facts actives

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This product is an over-the-counter drug as well as a cosmetic. It treats a cosmetic scalp condition; it does not diagnose or treat disease.

Ingredient list captured 2026-09-05. Formulas change — check the package in your hand when an ingredient matters to you.

Price · 1 oz

Commonly seen about $24 Midpoint $24 · 3 stores · checked Sep 5

Good value under $4 Under $4.26/oz it costs less than three-quarters of the 7 products we score as doing the same job

Priced above the products that do the same job. Stores sell it above the $4 line; products that do this job typically go for about $18 at this size.

Show the price ladder

Price for 1 ozlower is better

Where we’ve seen it4 listings · 4 stores

Act+Acre (actandacre.com)
$24.00

1 oz · $24.00/oz

Sep 5Lowest per oz
Sephora
$24.00

1 oz · $24.00/oz

Sep 5
Act+Acre
$24.00

1 oz · $24.00/oz

Sep 5
REVOLVE
$24.00

1 oz · $24.00/oz

Sep 5

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

1 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.
Commonly seen is the middle half of current prices for the 1 oz at recognised stores — the cheapest quarter and the dearest quarter are left out, so one sale or one overpriced listing can’t move it.
Good value under $4 comes from the 7 products we score as doing the same job as this one. A quarter of them cost less than $4.26/oz; at 1 oz that is $4. Under that line you are paying less than most of them.
About $18 is what those same products typically cost at this size — the midpoint of their prices per ounce, scaled to 1 oz.

Formula

Formula score

3 of 10

Sold through specialty beauty at a price 3 products that do the same job undercut — the counter is part of what you are paying for.

How the score is counted

3 products that do the same job cost less per ounce
Costs more per ounce than 81% of the 152 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 is completeness for the job: the share of the systems this product type is normally built around that we can find in this list, weighted. It is not efficacy, not quality, and it never compares across product types.

Does the same job, for less

Same derived functions — what it cleans, conditions, coats or holds — at a lower cost per ounce. Scent, texture and where you buy it can still differ.

BiolageClosest function Scalp Sync Purifying & Exfoliating Concentrate $4.13/oz $19.87/oz less

Vegan & CF

Differs: Cruelty-free
Vegan
Salon tier

Compare

Bread Beauty SupplyClose function Scalp-Serum: Cooling Greens Exfoliating Scalp Treatment $4.38/oz $19.62/oz less

Differs: Mint scent
Salon tier
1.7 oz bottle

Compare

MizaniLowest cost per oz Scalp Care Soothing Serum $2.83/oz $21.17/oz less

Fragrance-free
Protein-free
Lightweight

· Close function

Function: Hard-water defence
Also: 4 oz bottle
Sold through salons

Compare

See more alternatives in the product library

These are functional neighbours, not personal recommendations — they are close on formula, not chosen for anyone. Get the one that fits your hair, routine, and budget

Final decision

Should you buy it?

Good for the right person, not the lowest cost

Best user

People sensitive to fragrance, looking for a formula with no added fragrance and a protein-free formula

Biggest tradeoff

Not ideal for very dry or very humid climates

Best alternative if not

Biolage Scalp Sync Purifying & Exfoliating Concentrate, 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, against what the formula shows

Claims are quoted from the brand. We only mark one supported, partly supported, or conflicting when the ingredient list actually speaks to it; everything else stays "stated by the brand", which is not a criticism — most claims simply cannot be read off a label.

SupportedBacked by ingredients

Partly supportedSome supporting logic

Stated by brandNo clear evidence

Potential conflictFormula works against claim

Instantly hydrates + relieves dry scalp

Humectants or rich emollients sit in the first eight ingredients.

Pentylene Glycol
Propanediol
Glycerin

Supported

Helps hair feel hydrated.

Strengthens hair + scalp barrier

No protein or bond ingredient appears in the list.

Arginine
Aspartic Acid
Glycine

Stated by brand

Can’t be confirmed from label.

Supports sustained scalp health

Scalp comfort is not something an ingredient list settles.

Pentylene Glycol
Propanediol
Glycerin

Stated by brand

Depends on your scalp.

How to read this

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

Reviewers

What people report

Recurring themes our researchers wrote in their own words from sourced reviews. We do not store or scrape star ratings.

Reviewers repeatedly say this hydrating serum does not leave hair or scalp feeling greasy or oily, which surprises them for something this hydrating

reviewers commenting on daily use

Multiple reviewers report meaningful relief from a dry, flaky or itchy scalp, often describing it as instant

reviewers with chronic dry or itchy scalp

Some reviewers with diagnosed or sensitive scalp conditions say it calms their scalp without making the underlying condition worse

reviewers who named a specific scalp condition (e.g. seborrheic-dermatitis-type sensitivity)

How this page was made

Everything above is generated from our researched product record — identity, the ingredient list as printed, the brand's own claims, dated price observations, and review themes written in our researchers' own words. No part of this page is written per 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.
4 sources consulted for this product (1 manufacturer or regulatory, 0 retailer, 3 editorial), last checked 2026-09-05.
Ingredient references are linked for 10 of 21 product-aware annotations on this page. Fit notes are conditional formulation guidance, not a conclusion about the finished product or about you.
We have not tested this product in a lab and we do not physically test your hair. Formula readings come from the ingredient list; behaviour claims are labelled as the brand's.
Ingredient order tells you relative amount only above roughly 1%. Prices are observations on the dates shown and change without notice.
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 v22. Record last updated 2026-09-05.

Daily Hydro Scalp Serum with Hyaluronic Acid

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

Drug facts actives

Should you buy it?

What the brand says, against what the formula shows

What people report

More from Act+Acre

How this page was made

Your personalized hair plan