PRESERVATIVE
Dehydroacetic Acid
- preservative
A preservative used with benzyl alcohol as a paraben-free system.
- products in our library
- 95
- of researched products
- 2%
- on the label, in our shampoos
- usually #27
- most common in
- Shampoo
- in water
- Water-soluble
At a glance
Four things worth knowing about how this ingredient behaves on hair.
How much of it is left on hair between washes.
What it takes to get it off the hair again.
What it is in the formula to protect.
Where it sits on the labels we have, in the category it appears in most.
| Property | Level | Out of |
|---|---|---|
| Buildup risk | Low | 1 of 5 |
| Rinse-out behaviour | Rinses clean | 5 of 5 |
| Role | Keeps water-based formulas | 4 of 5 |
| Prominence | Secondary | 2 of 5 |
What it does for a formula
What Dehydroacetic Acid does
The general function first, then how the role changes by product type where we have researched it.
Anything with water in it needs one, over the life of the bottle.
Water alone removes it, so it does not accumulate between washes.
Charge
Charge is not recorded for this ingredient.
Solubility
Rinses out with water alone — it does not accumulate on hair between washes.
Where it appears
Where it appears
One row per product category in our library: how many products list it, what share of that category that is, and where it typically sits on the label.
| Product type | How common | Typical position on label ? |
|---|---|---|
Shampoo
26 products
|
secondary · #27 | |
Leave-in
15 products
|
secondary · #18 | |
Conditioner
12 products
|
secondary · #32 | |
Mask / treatment
11 products
|
secondary · #24 | |
Co-wash
6 products
|
secondary · #15 | |
Heat protectant
6 products
|
secondary · #18 | |
Styler: gel
5 products
|
secondary · #16 | |
Styler: smoothing cream
3 products
|
secondary · #33 | |
Finisher: shine spray
2 products
|
secondary · #10 | |
Styler: mousse
2 products
|
secondary · #21 |
6 more product types
| Product type | How common | Typical position on label ? |
|---|---|---|
Styler: volumizer
2 products
|
secondary · #13 | |
Finisher: serum
1 product
|
secondary · #20 | |
Scalp treatment
1 product
|
secondary · #20 | |
Styler: curl cream
1 product
|
secondary · #17 | |
Styler: edge control
1 product
|
secondary · #27 | |
Styler: texture spray
1 product
|
supporting · #8 |
| Product type | Products | Share of category | Median position | Earliest position | Band |
|---|---|---|---|---|---|
| Shampoo | 26 | 3% | 27 | 12 | secondary |
| Leave-in | 15 | 3% | 18 | 10 | secondary |
| Conditioner | 12 | 2% | 32 | 15 | secondary |
| Mask / treatment | 11 | 3% | 24 | 15 | secondary |
| Co-wash | 6 | 6% | 15 | 13 | secondary |
| Heat protectant | 6 | 4% | 18 | 13 | secondary |
| Styler: gel | 5 | 3% | 16 | 9 | secondary |
| Styler: smoothing cream | 3 | 5% | 33 | 33 | secondary |
| Finisher: shine spray | 2 | 3% | 10 | 9 | secondary |
| Styler: mousse | 2 | 1% | 21 | 12 | secondary |
| Styler: volumizer | 2 | 3% | 13 | 9 | secondary |
| Finisher: serum | 1 | 1% | 20 | 20 | secondary |
| Scalp treatment | 1 | 1% | 20 | 20 | secondary |
| Styler: curl cream | 1 | 1% | 17 | 17 | secondary |
| Styler: edge control | 1 | 6% | 27 | 27 | secondary |
| Styler: texture spray | 1 | 2% | 8 | 8 | supporting |
No product-type differences have been researched yet — the reading below is computed from where it sits on the labels in our library.
Position footprint
Every listing in our library, by position on the label.
| Positions | Zone | Listings |
|---|---|---|
| 1-3 | Leading | 0 |
| 4-8 | Supporting | 1 |
| 9-15 | Secondary | 20 |
| 16-25 | Lower | 43 |
| 26+ | Trace | 51 |
How to read this
US labelling rules put ingredients above 1% in descending order of amount; below 1% they may be listed in any order.
So position tells you about relative amount only above that line, and we never convert a position into a percentage.
Why it matters to shoppers
What this ingredient is evidence of, what it is not evidence of, and what our own method can and cannot tell you.
- a product that keeps over its shelf life
- a rinse-clean feel
- an exact safety score — we do not publish one, for any ingredient
- how a finished product performs by itself — that is the whole formula, not one line of it
- the exact percentage in a bottle — label position never converts into a number
- a secondary preservative, listed below the main ingredients in our shampoos
- it was on the label of every product we counted — we read printed ingredient lists, not marketing copy
- that the product would be better without one
- that a product is right or wrong for you
We do not publish safety scores or hazard grades. Where a regulator has published a restriction or a use condition, we state it and cite it; otherwise we describe what the ingredient does and stop.
Commonly paired with
Ingredients that appear alongside this one most often in our library. Near-universal ingredients are excluded — they pair with everything and tell you nothing.
- Benzyl Alcohol · 77
- Cetrimonium Chloride · 41
- Aloe Barbadensis Leaf Juice · 36
- Guar Hydroxypropyltrimonium Chloride · 32
- Benzoic Acid · 31
- Cetyl Alcohol · 30
- Butyrospermum Parkii (Shea) Butter · 27
- Cocos Nucifera (Coconut) Oil · 24
- Persea Gratissima (Avocado) Oil · 21
- Behentrimonium Methosulfate · 21
The number beside a name is how many products in our library list both.
These ingredients tend to appear together to carry the formula and let it dry, improve feel after rinsing, and give the formula body and hold.
Found in these products
The most prominent placements first. The badge is the position on that product’s own ingredient list.
L'ange · Styler
Salt + Sea Texturizing Spray
#8 on the label · $5.00/oz
Fairy Tales · Styler
Curly-Q Spray Hair Gel
#9 on the label · $1.28/oz
Kenra Platinum · Finisher
Color Charge Spray Serum
#9 on the label · $3.94/oz
Kenra Professional · Styler
Platinum Thickening Glaze Density Building Crème
#9 on the label · $6.25/oz
Fairy Tales · Leave-in
Tangle Tamer Static Free Kids Detangling Spray
#10 on the label · $1.83/oz
Sexy Hair · Finisher
Healthy Sexy Hair Shine Show Blowout Spray - 5.1 oz
#11 on the label · $4.50/oz
amika · Shampoo
Bust Your Brass Cool Blonde Strength Repair Shampoo
#12 on the label · $3.15/oz
Aunt Jackie's · Leave-in
Half & Half Hydrating Silkening Hair Milk
#12 on the label · $0.91/oz
Fairy Tales · Leave-in
Coco Cabana Leave-In Sun Hair Spray
#12 on the label · $1.24/oz
got2b · Styler
Curled Flexible Curl Foam
#12 on the label · $1.64/oz
Sexy Hair · Heat protectant
Healthy Smooth Stunner Blowout Creme
#13 on the label · $3.83/oz
Uncle Funky's Daughter · Co-wash
Bye-Bye Buildup Cleansing Conditioner
#13 on the label · $1.87/oz
See all 95 products in the library that list Dehydroacetic Acid
Identity
What this entry is, and what our references call it.
Dehydroacetic Acid
- CAS 520-45-6
- PubChem 122903
- dehydroacetic acid
For your hair?
Whether Dehydroacetic Acid matters for your hair depends on your hair.
95 products in our library list itWhat this ingredient does, and where it sits on the labels we have researched.
A verdict on any product that contains it, and never a safety grade.
We do not physically test your hair. Everything above is read from the ingredient lists in our library and from published references — the consultation is what turns it into a plan.
References
Sourced Backed by a manufacturer or regulatory source.
This ingredient
- Manufacturer or regulatory PubChem — Compound identity: CID 122903, CAS 520-45-6, C8H8O4 · accessed 2026-08-28
How this page was made
- Every number above is counted from the ingredient lists in our own product library — 95 of 4008 researched products list this ingredient. Nothing on this page is written per ingredient.
- The dots are levels, not scores. Each one is read from what kind of ingredient it is — its chemical class, its charge, its solubility — or from where it sits on the labels we have.
- US labelling rules put ingredients above 1% in descending order of amount; below 1% they may be listed in any order. Position tells you about relative amount only above that line, and we never convert a position into a percentage.
- The prominence bands (leading, supporting, secondary) are the same ones the product pages use to read a single label, applied here to the median position across a category.
- We do not publish safety scores or hazard grades. Where a regulator has published a restriction or a use condition, we state it and cite it; otherwise we describe what the ingredient does and stop.
- Identifiers and references appear only when a published source is attached to this entry; where none is, the row is simply absent rather than filled in.
- This is cosmetic information, not medical advice, and nothing here diagnoses or treats a health condition.
- Entry last updated 2026-08-28. Product-page methodology: the product library.