What is Hair Porosity?

Simply put Hair Porosity is the ability for a hair strand to absorb and retain moisture. It is determined by how open or closed the hair cuticle is.

Or at least if you do a quick internet search on hair porosity that is what you will find.

Nothing will drive a curly girl mad faster than finding out they need to pay attention to yet another bit of hair science. Porosity is so confusing for so many and there is so much misinformation out there. The thing is if you understand what you need to use on your specific porosity, it means the difference between frizzy or greasy hair and beautiful healthy hair. Porosity is not just about curly hair it is about ALL hair…straight, wavy, curly, and coily. In this post, I am going to unpack the entire story on porosity, well at least everything I could find.

Disclosure: The product links in this post may be affiliate links. As an Affiliate, I earn from qualifying purchases, at no additional cost to you. Read my Terms and Conditions Page to learn more.

Click any product name I mention or the photo and the link will take you to the product page for purchase.

What is the Hair Cuticle:

Let’s start with the hair cuticle, the hair cuticle is the outermost layer of the hair shaft, it looks a little bit like shingles on a roof or pinecone petals. Which Lorraine Massey uses pinecones to explain in Curly Girl: The Handbook [1]. And that is exactly what the hair cuticle looks like under magnification.

Just like the pinecone petals that tighten up to protect itself from weather and the environment so does a healthy cuticle. A smooth pinecone represents a protected, well-hydrated, healthy, undamaged cuticle. While a fluffy and rough pinecone represents a cuticle that might be dry, damaged and in need of moisture or repair.

Hair Porosity Defined:

Hair porosity all over the interwebs is defined as the ability of the strand to absorb and retain moisture. Usually porosity is referred to in three levels as low, medium/normal, and high porosity. But the definition of the grades of porosity that hair colorists use was actually developed by hair stylist Thia Spearing. Yes, originally it was grades of porosity from 1-5, somewhere along the way it shifted in the curly girl community to low, medium, and high.

Anyway, her refined definition found in the American Board of Certified Hair Colorists Study Portfolio is: “In hair coloring terms, when we speak of porosity, we are actually discussing the structural integrity of the hair.”[2] This is the condition a hair colorist will evaluate when you sit in their chair for chemical treatments; they are looking at whether or not your hair can withstand heavy processes like bleach or permanents.

Hair Porosity Grading System:

1-5 grading system as observed on both WET and DRY hair.

Grade 1:

  • Compact tight cuticle
  • Minimal to no chemical treatment, exposure to excessive sun, or mechanical styling tools
  • Most likely the person’s natural hair color
  • Elasticity is very good with very little resistance to combing when wet
  • The root and the tips are close to the exact same color

Grade 2:

  • Slightly raised cuticle
  • Mild chemical treatments, some environmental exposure
  • May be up to 3 levels lighter than natural hair color
  • Good elasticity

Grade 3:

  • Moderately raised cuticle
  • Moderate exposure to chemical treatments and/or regular use of heat implements
  • May be up to 5 levels lighter than natural hair color
  • Resistance to combing without conditioning treatment; fair elasticity.

Grade 4:

  • Excessively raised cuticle
  • Excessive exposure to chemical treatments and heated styling implements
  • Frizzy appearance when dry
  • May be up to 7 levels lighter than natural color
  • Poor elasticity and retangles when combed wet

Grade 5:

  • Loss of cuticle layer
  • Extreme exposure to chemical treatment to the point of breakage
  • Hair feels mushy or slimy when wet.
  • May be 8 or more levels lighter than natural hair color
  • No elasticity, breaks off when wet
  • The root and the tips are not the same color [2]

Using this Grading system:

  • Grades 1-2 are Low Porosity,
  • Grade 3 is Medium or Normal Porosity,
  • Grades 4-5 are High Porosity.

What changes hair porosity?

  • Length and age
  • Extended and regular exposure to sun
  • The pH of Hair Products
  • Chemical Processes
    • Permanents
    • Highlights and Bleaching
    • Hair dye
    • Relaxers
    • Blow outs (like Brazilian Blowout)
  • Heat styling: with Flat irons, curling irons, blow dryers
  • Environmental exposure: pollution, wind, dry climates and winter air

There are several things that can change porosity from low to high.

Once the damage is done the cuticle can be protected from further damage or it can grow out and be trimmed off, but it cannot be reversed.

The worst Grade 5 situation will usually result in a chemical haircut, where the hair is so damaged it is breaking off at the root.

Length and age:

The length and age of the hair affects porosity. The roots are usually going to be in the lower porosity grades because it is new fresh growth; the longer the hair is and the further it is from the scalp the higher the porosity can get at the tips. So if you are mid gray hair transition at about a year into your grow out, above the demarcation line will be Grade 1 or 2 and below the demarcation line can be anywhere from Grade 3 to 5 depending on what processes you were doing before you completely ditched the dye.

Image of Joli Campbell with info on hair porosity

How do you determine your hair porosity?


Let’s Start With the Float Test:

I didn’t know a thing about porosity until the last couple of years, and I was wrong about what I learned…I mistakenly believed the float test was accurate. While the concept is good, the method is fallible. The theory is that if you take a strand of hair and it floats, it is low porosity, if it sinks to the middle it is medium porosity and if it sinks all the way to the bottom, it is high porosity. This would be more accurate on clarified hair with absolutely nothing else on it. There are other issues as well, like water surface tension, natural oils from the scalp, hair texture, the age of the hair, hair dye or bleach, product buildup like silicones, etc.

In addition, if you are in the middle of growing out your dyed hair to your natural gray hair you have two or possibly three porosities.

The Strand Test:

Take a strand of hair from each section of your head (front, midline or crown, and nape) stretch the individual hair out and run your fingers from the tip up to the root.

  1. If it feels smooth and slick it is somewhere between Grade 1 & 3
  2. If it feels rough and dry (or breaks) it is somewhere between 4 & 5

For me this is a difficult test to perform because my hair is very fine in some places, so it is hard to feel an individual strand with my fingertips.

Kitsch Spray Bottle for Hair

The Fine Mist Spray Test:

I modified what is usually referred to as the Spray Bottle test to use a Fine Mist Spray Bottle for the super fine mist. Take a Fine Mist Spray Bottle and spray a section of your clean, dry, product free hair. If your hair has beads of water sitting on the shaft or rolling off immediately, that is Grade 1-2 porosity hair. If your hair soaks up the water after about a second or two, that is Grade 3 porosity. If your hair soaks up the water immediately like a sponge, that is Grade 4-5 porosity.

This is how I finally figured out my porosity. I had heard forever that low porosity hair was hard to get wet and hard to dry. I always thought my hair was easy to get wet and hard to dry. My hair immediately gets wet in the shower, what I didn’t realize is because it is so fine a heavy and full blast of warm water was going to soak it quickly. But with the Fine Mist Spray Test I could see that fine layer of mist turns immediately to beads of water and slowly begins to drip off.

How does pH affect Porosity?

pH is a measurement scale of acidity (stomach acid) to alkalinity (drain cleaner). The natural pH of virgin hair is somewhere around 4.5-5.5 which is slightly acidic. Chemical processes will push it from acidic to a more alkaline state. Which means higher porosity hair Grade 4-5 is more alkaline and can be upwards to a pH of 8-10. So a high pH substance opens the hair cuticle and a low pH substance will help smooth and seal the cuticle.

This is why it is sometimes a great idea to try an entire line-up of products from one brand. Ideally, they have started with shampoo being slightly more alkaline, moving down to more acidic for conditioner; as you reach the leave-in conditioner stage, it should be a pH that matches the normal pH of hair. Fairy knots happen to be one of the first signs your products are not pH balanced for your hair. [3]

You can learn more about pH in my full post: The Ultimate Guide to pH Balance for Hair and Why it Matters

QuickSilverHair pH Chart

pH of Different Porosities

On low porosity hair, alkalinity from baking soda washes will help open the cuticle and allow moisture in. Acidic products like vitamin C will work to tighten the cuticle even more which will dry out low porosity hair. Natural oils and butters should be used sparingly as they can overly coat the shaft and create weighed down hair. But thinner lighter oils can be used to grab fly-aways and smooth the halo.

On high porosity hair, apple cider vinegar rinses will help seal the cuticle and lock in moisture. Protein treatments help fill in the gaps in the open cuticles and strengthen the hair. Natural oils and butters used regularly can help create a protective barrier from the elements helping the hair to retain moisture and seal the cuticle, but beware of over conditioning. [4]

You can use pH test strips to test your products or you can call the company and ask if they know the pH of the products.


So what is your porosity and what do you do with that information?

With the grading system in mind, if you are fully transitioned to silver and using little to no heat you would fall in the Grade 1 or 2 porosity zone, unless you have naturally high porosity, which I believe is very rare. Try the Fine Mist Spray test and see how the water reacts on your hair. Or you can take a quiz on NaturallyCurly.com that helps better define and understand your hair type including curl pattern.


Click On Your Porosity for A Printable PDF Characteristics and Tips Sheet

Video Series on Porosity

Shop Your Porosity Type

Click any button below to purchase on Amazon.com

I want to give a huge shout-out to Manes By Mel, because of her video Porosity Test Mistakes People Make + How to Test Your Porosity Properly I was able to find the info I needed for letting you know what porosity really is.

I hope this post helped clear up some confusion and gave you the information you need to make choices in your hair care that help you achieve your most beautiful and healthy hair. Straight, Wavy, Curly, Coily…Have a Great Hair Day.

Photo of Joli Campbell


I hope you found this post educational and helpful.

Thank you for reading. Please feel free to share.

As always it is about so much more than the hair.








Next Suggested Post

The Ultimate Guide to pH Balance for Hair and Why it Matters

*Affiliate Links:

QuickSilverHair is a participant in the Amazon Services LLC Associates Program. Some of the links on this site are affiliate links to Amazon.com. I earn money as an Amazon Associate from qualifying purchases.

QuickSilverHair is an affiliate with several brands, I earn a small percentage from any qualifying purchases, at no additional cost to you.

© Copyright disclaimer: All content is written by Joli A. Campbell or Guests, that content belongs to QuickSilverHair or the respected author. All Images in this blog belong to the women in the picture, myself, or were used with purchase or commercial permissions. I have used their images and names with their permission. Please do not copy or redistribute anything from this site without further permission. Thank you.

QuickSilverHair.com content disclaimer: content is provided for general information purposes and should not be considered medical advice. Product information is not intended to diagnose, treat, cure or prevent any disease. The hair care content is also for educational use, I am not a hair care professional or dermatologist, please be careful with your hair and skin. If you have any hesitations or concerns speak to your doctor or hair care professional for their support before using any information you find on this site. Be well.

For full Affiliate and Copyright Details Please Read My Terms & Conditions Page

  1. Massey, Lorraine, and Michele Bender. Curly Girl: the Handbook. Workman, 2011.
  2. “American Board of Certified Haircolorists Study Portfolio .”https://issuu.com/certification/docs/american_board_of_certified_haircolorists/5, Chapter 4 The Study of the Porosity of Hair.
  3. Walton, Charlene. “Why Your Moisturizer Doesn’t Work.” NaturallyCurly.com, 14 May 2015, naturallycurly.com/curlreading/home/chemist-obia-explains-the-importance-of-ph-balance.
  4. “3 Reasons You Can Blame Your Worst Hair Day On Porosity.” CarolsDaughter.com, 17 Nov 2016, https://www.carolsdaughter.com/blog/hair/natural-hairstyles/3-Reasons-You-Can-Blame-Your-Worst-Hair-Day-On-Porosity.html.

Pin It on Pinterest