- The scalp pH is 5.5, and the hair shaft pH is 3.67
- Hair is at its least vulnerable between about pH 4.5 and 6.5. Select products in this range if you have delicate, thin or fine, breakage-prone or damaged hair
- Check if your shampoo has the correct pH balance. If not:
- Request MSDS/SDS Safety Data Sheets from sellers: These will have the pH or pH range of the product. Cosmetic companies should have these available for consumers to access
- Search our shampoo pH Levels Database (270+ products list with popular brands)
Your hair’s pH balance plays a vital role in overall natural hair health

Despite what the hair product packaging might declare about “fruit extracts” or being “sulfate-free,” the single biggest factor determining whether a shampoo will make your hair shiny, manageably and healthy is its pH level.
For those who didn’t ace science in school, pH is a numeric scale ranking how acidic a substance is. Anything with a level under 7 is acidic, and solutions with a pH more than 7 are labelled basic or alkiline.
The scalp pH is 5.5, and the hair shaft pH is 3.67.
Shampoos at a lower pH (4.5 – 6.5) preserve your hair and scalp’s natural oils, which exist to protect against frizz-causing damage.
Note: It’s likely safe to keep products in this range if you have delicate, thin or fine, breakage-prone or damaged hair.
At the optimal pH, shampoo doesn’t completely remove all the natural oils, so you avoid over-drying the scalp, something Dr. Barbara Olisio, a cosmetic scientist who formulates hair and skin products, says causes “a vicious cycle that actually triggers more sebum production.”
The scalp and hair have an efficient mechanism to protect itself that is based on lipids, functioning at its best at low pH. At low pH, the hair cuticles are well-sealed so that the hair is stronger and shinier.
Dr. Barbara Olisio Cosmetic scientist – News Australia
Where to find pH of your hair products?
Determining a shampoo’s pH level ( or acidity) is hard, unless it’s clearly labelled on the bottle. There is no legal obligation for the industries to mention pH level on the label.
Some are, by the way, while others claim to be “pH-balancing” but remain shady about the product’s exact level. Here are some helpful resources:
- MSDS/SDS Safety Data Sheets: These will have the pH or pH range of the product listed. Cosmetic companies should have these available for consumers to access. Not all can be found online, but with a little digging you can find them for the majority of products.
For example, paul mitchell product sheets can be easily found here: http://www.paulmitchellpro.com/safety-data-sheets.php
Paul Mitchell Awapuhi Shampoo Safety Data sheet:

P&G has theirs listed in this database: https://pgproductsafety.com/productsafety/
Aussie Miracle Volume Shampoo Safety Data Sheet:

Note: pH is given in a range because it may vary from batch to batch or product to product, though the pH needs to be in a specific range in most cases in order for preservatives to be effective and the product to be stable on the shelf.
- Test pH at home:
Get yourself some pH strips in the aquatic pets section of a pet store or the swimming pool section of a department store, or from your local drugstore. Make sure they measure below pH 7 as well as above.
Please note that conditioner often gives a less-than-accurate reading because it’s not all liquid (there are fats in there). But you can get a rough idea.
- Search our shampoo pH Levels Database (270+ products list with popular brands)
Scientific Research about pH and Hair
Scientists from the Department of Dermatology, Instituto de Dermatologia Professor Rubem David Azulay, reviewed the current literature about the mode of action of a low-pH shampoo regarding the hair shaft’s health and analyzed the pH of 123 shampoos of international brands. [PubMed]
- Alkaline pH (>7 pH) may increase the negative electrical charge of the hair fiber surface and, therefore, increase friction between the fibers. This may lead to cuticle damage and fiber breakage. It is a reality and not a myth that lower pH of shampoos may cause less frizzing for generating less negative static electricity on the fiber surface.
- All tested shampoo pH values ranged from 3.5 to 9.0.
- Only 38% of the popular brand shampoos presented a pH ≤ 5.0.
- Pediatric shampoos had the pH of 7.0 because of the “no-tear” concept. 100% of the children’s shampoos presented a pH > 5.5.
- 61.78% presented a pH > 5.5
We don’t keep our haircare secrets.
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