Side by side
Biolage Scalp Sync Purifying & Exfoliating Concentrate vs Nioxin Night density Rescue Serum
92% function match · 6 of the 7 functions we compared match Formula overlap 13%. Biolage Scalp Sync Purifying & Exfoliating Concentrate and Nioxin Night density Rescue Serum share 1 ingredient 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.
- Scalp Sync Purifying & Exfoliating Concentrate — vegan and cruelty-free
- Night density Rescue Serum — protein-sensitive 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”.
Compared at different sizes — 6.8 oz against 2.3 oz. Per-ounce prices favour the larger bottle.
- Vegan and cruelty-freeour researched record has it as both
- Protein-sensitive hairthat stiffens when protein is added
- Fine hairthat flattens under most products
- Silicone-free routinesno silicones appear in the list
- Easy to findsold through several channels
- Scents bother youthis product carries a scent
- Very dry or damaged hairit contains fast-drying alcohol
- Dry or very humid airwhere heavy humectants work against you
- Scents bother youthis product carries a scent
- Very dry or damaged hairit contains fast-drying alcohol
- Vegan and cruelty-freeour record does not support both claims here
More facts about each one
- sulfate-free
- silicone-free
- protein-free
- curly-method compatible
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.
$49.00 once, for your consultation and hair profile. No subscription, no required purchases.
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
Scalp Sync Purifying & Exfoliating Concentrate
- Hydroxyethylpiperazine Ethane Sulfonic Acid
- Propanediol
- Glycolic Acid
- Sodium Hydroxide
Night density Rescue Serum
Full ingredient list — Scalp Sync Purifying & Exfoliating Concentrate (21)
-
1
Water
- solvent
-
2
Alcohol Denat.
- drying alcohol
- solvent
-
3
Butylene Glycol
- humectant
- solvent
- 4 Hydroxyethylpiperazine Ethane Sulfonic Acid
-
5
Propanediol
- humectant
- solvent
- Below about this point, order stops being meaningful — these are typically used at 1% or less.
-
6
Glycolic Acid
- exfoliant
- pH adjuster
-
7
Sodium Hydroxide
- pH adjuster
-
8
PEG-40 Hydrogenated Castor Oil
- solubilizer
- emulsifier
-
9
Caprylyl Glycol
- preservative
- humectant
-
10
Potassium Sorbate
- preservative
-
11
Fragrance
- fragrance
- declared fragrance
-
12
Tetrasodium Glutamate Diacetate
- hard-water chelator
-
13
Saccharomyces/Xylinum/Black Tea Ferment
- botanical extract
-
14
Propylene Glycol
- humectant
- solvent
-
15
Limonene
- fragrance
- named fragrance allergen
-
16
Glycerin
- humectant
-
17
Sorbitol
- humectant
-
18
Camellia Sinensis (Green Tea) Leaf Extract
- botanical extract
- antioxidant
-
19
Citric Acid
- pH adjuster
- hard-water chelator
-
20
Sodium Benzoate
- preservative
-
21
Ascorbic Acid
- antioxidant
- vitamin
Full ingredient list — Night density Rescue Serum (25)
-
1
Alcohol Denat.
- drying alcohol
- solvent
-
2
Water
- solvent
-
3
Caffeine
- active
-
4
Panthenol
- humectant
- conditioning agent
- vitamin
- Below about this point, order stops being meaningful — these are typically used at 1% or less.
-
5
Fragrance
- fragrance
- declared fragrance
-
6
Menthol
- fragrance
- active
-
7
Lauric Acid
- emulsifier
-
8
PEG-40 Hydrogenated Castor Oil
- solubilizer
- emulsifier
-
9
Tocopheryl Acetate
- antioxidant
- vitamin
- 10 PEG-35 CASTOR OIL
-
11
Butylene Glycol
- humectant
- solvent
-
12
Propylene Glycol
- humectant
- solvent
-
13
Linalool
- fragrance
- named fragrance allergen
-
14
Polysorbate 20
- solubilizer
- emulsifier
-
15
Zingiber Officinale (Ginger) Root Extract
- botanical extract
-
16
Hexyl Cinnamal
- fragrance
- named fragrance allergen
-
17
Limonene
- fragrance
- named fragrance allergen
-
18
Citronellol
- fragrance
- named fragrance allergen
-
19
Passiflora Edulis Fruit Extract
- botanical extract
-
20
Geraniol
- fragrance
- named fragrance allergen
-
21
Potassium Sorbate
- preservative
-
22
Sodium Benzoate
- preservative
-
23
Citral
- fragrance
- named fragrance allergen
-
24
Sorbic Acid
- preservative
-
25
Farnesol
- fragrance
- named fragrance allergen
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.
Scalp Sync Purifying & Exfoliating Concentrate
Exfoliates and clarifies scalp after one use
Stated by brandCan’t be confirmed from label.Removes buildup, excess oil, impurities, and dead skin
Stated by brandCan’t be confirmed from label.Suitable for sensitive scalps and color-treated hair
Stated by brandCan’t be confirmed from label.Soothes and hydrates scalp for up to 72 hours
SupportedHelps hair feel hydrated.
Night density Rescue Serum
Lightweight and non-greasy
SupportedLess likely to weigh hair down.
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.
Nioxin Night density Rescue Serum draws complaints about the packaging.
Scalp Sync Purifying & Exfoliating Concentrate
several reviewers with dry, itchy or eczema-affected scalps report significant relief after weeks of consistent use
reviewers with chronic dry/itchy scalp conditionsmany reviewers with oily or buildup-prone scalps say it visibly reduces oil and extends time between washes when used weekly
reviewers with oily scalp, often paired with the matching shampoo/conditionerreviewers repeatedly describe the texture as very thin and watery, making it hard to control and easy to overuse or spill
general reviewersa recurring caution among reviewers is the product's sun-sensitivity warning, which several found off-putting or worrying for summer use
reviewers noting the AHA sun-sensitivity labelseveral reviewers who did not see results for dandruff or oiliness still praised the scent and the ritual feel of the pre-wash step
reviewers unconvinced of efficacy but positive on sensory experienceNight density Rescue Serum
Users often find the liquid light and non-greasy for overnight application.
US exact-product reviewer accounts; promotional sampling appears in the corpus. Review IDs: 1172115598, 1171689932, 1171580825, 1169661644Leaking bottles and difficult dispensing recur in packaging complaints.
US exact-product reviewer accounts; promotional sampling appears in the corpus. Review IDs: 1169690823, 1169555383, 1168103122, 1148458466Some users report scalp tenderness, itching or a burning sensation.
US exact-product reviewer accounts; promotional sampling appears in the corpus. Review IDs: 1172271437, 1169507711, 1153761231Reports of fuller-looking hair are mixed with reports of no visible difference after several weeks.
US exact-product reviewer accounts; promotional sampling appears in the corpus. Review IDs: 1175637429, 1171789190, 1172271437, 1169661644, 1148458337Price 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.
$4.13/oz vs $21.10/oz — Nioxin Night density Rescue Serum costs about 5.1× more per ounce than Biolage Scalp Sync Purifying & Exfoliating Concentrate.
Every mark sits on one distribution because these are compared against the same set: 154 scalp treatments 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.
Scalp Sync Purifying & Exfoliating Concentrate · Night density Rescue Serum · All scalp treatments 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.
- 11 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.
- This particular combination is not listed in our sitemap: we only submit pairs of comparable products that our similarity data says people would actually weigh against each other.
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