Side by side
Function of Beauty Straight Hair Shampoo vs Redken Acidic Bonding Concentrate Shampoo
94% function match · 11 of the 13 functions we compared match Formula overlap 10%. Function of Beauty Straight Hair Shampoo and Redken Acidic Bonding Concentrate Shampoo share 3 ingredients among each other's most prominent.
Which of these fits your hair?
We check your pattern, moisture need, scalp, fragrance tolerance, weight sensitivity and more against each formula — and say which one lines up.
Your profile at a glance
- Your answers appear here
- Your answers appear here
- Your answers appear here
- Your answers appear here
When each one is the right call
What each formula is built for, from its own ingredient list.
- Straight Hair Shampoo — colour-treated hair
- Acidic Bonding Concentrate Shampoo — colour-treated hair
Side by side
Every trait, aligned
One row per trait, read from each product’s own ingredient list and record. A dash means we have not researched that field for that product — it is not a “no”.
- Colour-treated hairthat fades faster in a sulfate wash
- Protein-sensitive hairthat stiffens when protein is added
- Hard waterand swimmers dealing with mineral deposit
- Fine hairthat flattens under most products
- Colour-treated hairthat fades faster in a sulfate wash
- Protein-sensitive hairthat stiffens when protein is added
- Hard waterand swimmers dealing with mineral deposit
- Fine hairthat flattens under most products
- Scents bother youthis product carries a scent
- Curly-method routinesthese silicones need a detergent to remove
- Hair that needs proteinthere is none in this list
- Scents bother youthis product carries a scent
- Curly-method routinesthese silicones need a detergent to remove
- Very dry or damaged hairit contains fast-drying alcohol
More facts about each one
- sulfate-free
- protein-free
- sulfate-free
- protein-free
Facts as we recorded them. A dash means we have not researched that field for that product — it is not a "no".
The bottom line
The bottom line depends on your hair
Which of these two suits you is a question about your hair, not about them. The consultation answers it — and tells you what your routine needs around it.
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The detail behind the table
Where the readings above come from: the ingredient lists themselves, each brand’s claims checked against them, what owners report, and cost per ounce in context.
Shared and distinct ingredients
Shared and distinct ingredients
Computed from the ingredient lists as printed. "Shared" means both lists carry it; where it sits on each label is stated, because position is what tells you how much.
What both formulas carry
What only one of them carries
Straight Hair Shampoo
Acidic Bonding Concentrate Shampoo
Full ingredient list — Straight Hair Shampoo (37)
-
1
Water
- solvent
-
2
Sodium Lauroyl Methyl Isethionate
- mild anionic cleanser
- cleanser
-
3
Glycerin
- humectant
-
4
Sodium Methyl Cocoyl Taurate
- mild anionic cleanser
- cleanser
-
5
PEG-120 Methyl Glucose Dioleate
- thickener
- emulsifier
-
6
Cocoamidopropyl Hydroxysultaine
- amphoteric cleanser
- secondary cleanser
- cleanser
-
7
Sodium Methyl Isethionate
- cleanser
-
8
Cocos Nucifera (Coconut) Fruit Juice
- botanical extract
-
9
Lauric Acid
- emulsifier
-
10
Acrylates Crosspolymer-4
- film former
- polymer
- thickener
- Below about this point, order stops being meaningful — these are typically used at 1% or less.
-
11
Trisodium Ethylenediamine Disuccinate
- hard-water chelator
-
12
Glycol Distearate
- opacifier
- emollient
-
13
Phenoxyethanol
- preservative
-
14
Sodium Chloride
- salt
- thickener
-
15
Propoxytetramethyl Piperidinyl Dimethicone
- silicone
- conditioning agent
-
16
Sodium Laurate
- light ester
- emollient
-
17
Methyl Gluceth-10
- humectant
- emulsifier
-
18
Caprylyl Glycol
- preservative
- humectant
-
19
Chlorphenesin
- preservative
-
20
Potassium Sorbate
- preservative
-
21
Polyquaternium-7
- conditioning agent
- film former
- polymer
-
22
Trideceth-6
- emulsifier
- solubilizer
-
23
C11-15 Pareth-7
- emulsifier
- solubilizer
-
24
Ethylhexylglycerin
- preservative
- emollient
-
25
Hexylene Glycol
- solvent
- humectant
-
26
Guar Hydroxypropyltrimonium Chloride
- conditioning agent
- polymer
- gum
-
27
Hydroxypropyl Methylcellulose
- gum
- thickener
- film former
-
28
Sodium Benzoate
- preservative
- 29 Sodium Benzotriazolyl Butylphenol Sulfonate
-
30
Citric Acid
- pH adjuster
- hard-water chelator
-
31
Fragrance
- fragrance
- declared fragrance
-
32
Citral
- fragrance
- named fragrance allergen
-
33
Citronellol
- fragrance
- named fragrance allergen
-
34
Limonene
- fragrance
- named fragrance allergen
-
35
Linalool
- fragrance
- named fragrance allergen
-
36
Blue 1 (CI 42090)
- colourant
- direct dye
- blue dye
-
37
Red 33
- colourant
Full ingredient list — Acidic Bonding Concentrate Shampoo (29)
-
1
Water
- solvent
-
2
Decyl Glucoside
- nonionic cleanser
- cleanser
-
3
Sodium Cocoyl Isethionate
- mild anionic cleanser
- cleanser
-
4
Cocamidopropyl Betaine
- amphoteric cleanser
- secondary cleanser
- cleanser
- Below about this point, order stops being meaningful — these are typically used at 1% or less.
-
5
Citric Acid
- pH adjuster
- hard-water chelator
-
6
Sodium Hydroxide
- pH adjuster
-
7
Panthenol
- humectant
- conditioning agent
- vitamin
-
8
Glycerin
- humectant
-
9
Dimethicone
- silicone
- emollient
- conditioning agent
-
10
PEG-150 Distearate
- thickener
- emulsifier
-
11
PPG-5-Ceteth-20
- emulsifier
- solubilizer
-
12
Sodium Benzoate
- preservative
-
13
Sodium Chloride
- salt
- thickener
-
14
PEG-55 Propylene Glycol Oleate
- emulsifier
- emollient
-
15
Propylene Glycol
- humectant
- solvent
-
16
Carbomer
- thickener
- polymer
- film former
-
17
Fragrance
- fragrance
- declared fragrance
-
18
Coco-Caprylate/Caprate
- light ester
- emollient
-
19
Polyquaternium-67
- conditioning agent
- film former
- polymer
-
20
Salicylic Acid
- active
- exfoliant
-
21
Amodimethicone
- silicone
- conditioning agent
- film former
-
22
Sodium Phytate
- hard-water chelator
-
23
Glycol Distearate
- opacifier
- emollient
-
24
Coco-Betaine
- amphoteric cleanser
- secondary cleanser
- cleanser
-
25
Acrylates/Beheneth-25 Methacrylate Copolymer
- film former
- polymer
-
26
Limonene
- fragrance
- named fragrance allergen
-
27
Trideceth-6
- emulsifier
- solubilizer
-
28
Alcohol Denat.
- drying alcohol
- solvent
-
29
Cetrimonium Chloride
- conditioning agent
- cleanser
Claims check
What each brand says, against what each formula shows
Claims are quoted from each brand. We only mark one supported, partly supported, or conflicting when that product’s ingredient list actually speaks to it.
Straight Hair Shampoo
93% naturally-derived
Stated by brandOnly the brand’s testing shows this.Sulfate-free, paraben-free, cruelty-free, 100% vegan
Stated by brandOnly the brand’s testing shows this.
Acidic Bonding Concentrate Shampoo
Protects hair from color-fading, damage & heat exposure
SupportedLess fade per wash.Revitalizes dull locks with strength & hydration
SupportedHelps hair feel hydrated.Intense conditioning for stronger and more resilient hair
Stated by brandCan’t be confirmed from label.Most concentrated all-in-one formula for strength repair for all types of damaged hair
Stated by brandCan’t be confirmed from label.Vegan & sulfate-free formula
SupportedGentler on colour and coils.
What owners say
What people report
Recurring themes our researchers wrote in their own words from sourced reviews. We do not store or scrape star ratings, and we never balance one product’s themes against another’s by inventing them.
Function of Beauty Straight Hair Shampoo draws complaints about dryness and breakage; Redken Acidic Bonding Concentrate Shampoo draws complaints about the packaging.
Straight Hair Shampoo
Reviewers with sensitive skin/scalp report the formula worked well for them
sensitive-skin reviewersSoftness and shine without heavy product buildup are frequently praised
Some reviewers report dryness and brittleness despite the sulfate-free formulation
Scalp irritation and itching are mentioned by a subset of reviewers
A cluster of reviewers report significant hair loss and breakage after regular use
Acidic Bonding Concentrate Shampoo
Users report the shampoo feels salon-quality and recommend it to family/friends
general usersReviewers describe hair as clean, silky, and smooth after use
general usersReviewers with fine hair report the 3-step system (shampoo, conditioner, leave-in) makes hair feel thicker and healthier
fine hairMultiple reviewers praise softness and nourishment without weigh-down concerns raised
general usersA recurring complaint is damaged/leaking packaging during shipping, unrelated to the product formula itself
general usersPrice check
Cost per ounce, in context
Cost per ounce against every product of this type we have priced, each at the size it is most often sold in. Value labels are computed from that percentile and from how many products that do the same job cost less; they are comparisons, not judgements about a brand.
$0.94/oz vs $3.46/oz — Redken Acidic Bonding Concentrate Shampoo costs about 3.7× more per ounce than Function of Beauty Straight Hair Shampoo.
Every mark sits on one distribution because these are compared against the same set: 817 shampoos with a computable unit price.
Computed from cost per ounce against every product of this type we have priced, and from how many products that do the same job cost less. It is a comparison, not a judgement about the brand.
Compare with something else
Close formulas to each of these, as their own comparison pages.
Straight Hair Shampoo · Acidic Bonding Concentrate Shampoo · All shampoos in the library
How this page was made
- This page is assembled from the same researched records the individual product pages render: identity, each ingredient list as printed, each brand's own claims, dated price observations, and review themes written in our researchers' own words. Nothing on it is written per comparison.
- We do not rank these against each other. Which of them suits you depends on your hair, and that is what the consultation works out.
- The formula similarity percentage is a stored, precomputed number: position-weighted overlap of the two ingredient lists blended with agreement on the attributes we derive. It measures how alike two formulas are, not how well either works.
- 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.
- 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.
- 7 sources were consulted across the products on this page.
- Ingredient order tells you relative amount only above roughly 1%. Prices are observations on the dates shown and change without notice. We do not sell these products and take no placement fees.
- This is cosmetic information, not medical advice, and nothing here diagnoses or treats a health condition.
Still unsure? Take your consultation or browse more products.
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