There are a variety of terms used to describe hair type. We can call it straight, wavy, curly, frizzy, kinky, woolly, etc. However, these terms can be vague and confusing, as their definitions are not always clear. To more accurately define the hair type, it is necessary to use more precise assessments.
This article will give you an overview of the most commonly used method to classify hair, tips to identify your specific type and care recommendations for each type.
Why is it important to know your hair type?
Correctly identifying your hair type is an important first step in addressing hair issues. Different hair types have different structures and chemical compositions, which can affect their appearance and behaviour. Knowing your hair type will allow you to create a customised hair care plan and helps you avoid problems like shedding and thinning.
The different types of hair
There are different ways hair science classifies hair. In this article, we will introduce the method that’s most commonly used by hair professionals to provide hair care tailored to the individual’s unique needs.
This method was created by stylist Andre Walker in his 1997 study (Walker et al., 1997) and it is based on the shape of the hair. This approach gets rid of outdated methods, and instead focuses on capturing the variations within hair shape patterns.
Walker identifies 4 main types:
- Type 1: Straight
- Type 2: Wavy
- Type 3: Curly
- Type 4: Kinky/Coily
Recognising the variety in different hair shapes, he also adds further sub-categories within each type, which he calls A, B, and C. While the sub-categories within each type have the same shape, they vary in thickness, texture, or pattern of curl. For example, he describes Type 1A as straight, fine, and thin, while 1C is as straight, coarse, and frizzy.
Figure 1. A summary of hair types based on Walker's method.
Note: Walker’s original method didn’t include C categories for Type 3 and 4 hair, but we added them as the types have since been expanded.
Let’s take a closer look at each type to better understand how to identify and best care for them!
Type 1: Straight hair
Straight hair is characterised by a lack of curl pattern. It lies flat on the scalp and is smooth to the touch. The straight pattern allows natural oils to easily travel down the strands, giving the hair a shiny, lustrous appearance. Within the category of Type 1 hair, there are three sub-categories.
Figure 2. An example of straight hair. There are no bends and the surface of the hair is smooth.
Type 1A hair is fine and fragile. It is super straight and doesn’t hold waves and curls. The natural oils travel freely from the scalp and the hair texture is fine. As a result, Type 1A hair has a shiny, lustrous look, but it can also get greasy more easily and quickly than other types.
Type 1B hair is similar to Type 1A, but it’s more voluminous and has a thicker texture. As such, it holds waves and curls better than Type 1A.
Type 1C hair is straight, but it has a thick and coarse texture. It can get frizzy in humid climates and can have an untidy appearance if airdried.
How to take care of your straight hair
- Use natural hair products
Harsh chemicals can strip straight hair of its natural oils and damage its fine texture. Natural and gentle products usually work best for this hair type. As straight hair often looks flat and limp, try to avoid heavy products that can weigh it down. Opt for lighter and volumizing formulas instead to give your hair a fuller, fresher look.
- Wash your hair regularly
Regular washes are often advised against due to the damaging and drying effects of some cleaning agents. However, if the hair gets oily easily, it is important to clean the scalp regularly. Excessive oil, styling products, and dead skin cells can build up on the scalp, causing irritation and problems like dandruff or even shedding.
Choose a shampoo that’s suitable for frequent use and cleanses the scalp gently. This will keep your scalp fresh and create a healthy environment for hair to grow.
- Avoid sleeping with wet hair
Sleeping with wet hair can be damaging for all hair types. But Type 1 is especially fragile in this regard. If unavoidable, apply a light leave-in conditioner and put your hair into a loose braid before sleeping. This will minimise breakage and damage.
Type 2: Wavy hair
Type 2 or wavy hair lies between straight and curly on the scale. This type of hair forms an “S” shape (as opposed to curly hair, which forms a spiral shape). Type 2 hair is usually straight at the roots and the waves start to form from mid-length. As the oils don’t travel down the hair as easily as on straight hair, Type 2 hair tends to have drier ends.
Type 2A hair is fine and thin. It forms loose, S-shaped waves on drying. The hair appears straight at the root and wavy towards the end. Since this type of hair often has a mixture of straight and wavy parts, it can easily be straightened or curled.
Type 2B has more well-defined waves than 2A. The hair may appear straight from the scalp, and the waves get prominent in the middle. It also has a thicker, coarser texture than 2A, and as such, it tends to be frizzier. This type of hair is ideal for creating romantic and soft hairstyles, as it holds curls well.
Type 2C hair’s texture is thick, coarse, and frizzy. It has a well-defined wavy pattern, which can appear almost curly. Unlike the other two wavy types, the waves for 2C can start at the roots just like curly hair.
If you are unsure whether your hair is Type 2C or curly, the direction of growth might be a good indicator. While curly hair expands sideways as it grows, the direction of growth for 2C is more downward.
Figure 4. A scientific approach. The number of bends over a certain length can be determining factor in hair types.
[Source: Shape Variability and Classification of Human Hair: A Worldwide Approach]
How to take care of your wavy hair
- Be gentle with your hair
Detangling wavy hair can be a big task sometimes. Use your fingers to detangle them or a wide-tooth comb to prevent your hair from breaking. When hair is extremely tangled, it’s best to start detangling and combing from the bottom and work your way up. This will help you avoid breakage and damage.
- Nourish your hair
It is important to nourish wavy hair regularly. As natural oils don’t travel down wavy hair as easily as straight hair, it can get dry if not looked after properly. Use a silicone-free conditioner with nourishing ingredients. This will help you detangle the hair while washing it and keep it shiny and bouncy for longer.
- Use silk pillowcases or caps for sleeping
As wavy hair is prone to tangling, it must be treated carefully, especially at night. Rough fabrics and tossing and turning can tangle it even more. To keep your hair as smooth as possible, use a silk pillowcase or cap while sleeping.
Want to learn more about other sleep habits that might damage your hair? You can read more about them here.
Type 3: Curly hair
Type 3 hair has well-defined, spiral curls that look similar to ringlets. The hair appears curly from the roots and has more body than wavy hair. The curls make it hard for natural oils to travel down the hair, so curly hair is prone to dryness, frizziness, and breakage.
Figure 5. Type 3 hair has visible curls from the roots to the tips. The curls are spring-like, which makes the hair bouncy and voluminous.
Type 3A hair has big, loose, and bouncy curls. The hair is finer and often shinier than other Type 3s, but it’s still prone to frizziness. Type 3 hair can define its curls without styling products, and it is the most easily manageable among curly hair types.
The curls of Type 3B are tighter than 3A, usually medium to tight curls. It usually has a thicker texture and higher density than Type 2A. The hair looks voluminous, but it can be challenging to style as it’s frizzy and requires regular moisturising.
Type 3C hair has small, spring-like curls that are packed very tightly. This gives the hair a voluminous look and a thicker texture. As a result, Type 3C hair requires even more moisture and hydration than other curly types.
How to take care of your curly hair
- Give your hair the hydration and moisture it needs
Proper hydration and moisturisation are key to keeping curly hair healthy. As the curls don’t allow natural oils to travel down the hair, it is important to regularly nourish this hair type. Thicker conditioners, treatments, and oils can help you manage frizz and avoid breakage.
- Choose a shampoo with nourishing ingredients
In addition to proper hydration and moisturisation, it is also essential to choose the right shampoo that doesn’t dry out the hair. Opt for a sulphate-free option with nourishing ingredients and try to focus it the product on the roots instead of the length of the hair. This will help you keep your locks bouncy and full of life.
- Minimise the use of heat and chemicals
Curly hair is prone to damage and breakage, so to keep it healthy, it’s best to minimise the use of heat tools or chemicals. If you do use heat on your hair, make sure to apply heat protection.
Don't have a reliable heat protectant yet? Why not take a look at our Hair Protection Oil? In addition to frizz-controlling properties, it helps you resist heat up to 230 °C.
Type 4: Kinky or coily hair
Type 4 hair consists of tightly coiled curls or Z-angled coils, which are densely packed. In comparison to curly hair, coily hair has significant shrinkage. It can shrink to about as much as 80% of its original length. Type 4 hair is the most fragile of all types as the curl pattern doesn’t allow natural oils to travel down the hair. As a result, coily hair usually appears more matt than other types, and it requires regular conditioning - often daily - to maintain its shine.
Figure 6. An example of typical Type 4 hair. The hair has a matt look with tightly packed coils that aren't clearly defined.
Type 4A hair has very tightly packed coils with a well-defined springy pattern. The circumference of the coils is about that of a crochet needle.
Instead of curls or coils, Type 4B hair bends in Z-shaped angles. The “curls” are tighter than 4A and are less defined.
Type 4C is similar to 4B, but the hair is more tightly coiled with less definition and more shrinkage. This type of hair is very delicate and requires a lot of attention. But by following a careful regime, this hair type can thrive just like any other.
How to take care of your coily hair
- Deep condition your hair regularly
Type 4 hair is the driest and most fragile type of all. So, in addition to nourishing shampoos and conditioners, this hair will benefit immensely from regular deep conditioning as well as a leave-in conditioner every or every other day.
- Use protective hairstyles
Coily hair can be especially sensitive to environmental factors that other types might tolerate better (sun, humidity, pollution, etc). Protective hairstyles, such as twists and braids, are an excellent choice to give your hair a break from these factors and keep if healthy for longer.
- Resist the temptation to straighten your hair
It can be tempting to straighten Type 4 hair. While it is not impossible, it requires a lot of heat, which can be highly damaging. If you do straighten your hair, make sure to use a high-quality tool and a heat protectant to avoid damage as much as possible.
Tips to correctly identify your hair type
The above guide will help many people to identify their hair type. However, everyone’s hair is unique, and some types might be more challenging to identify than others.
If you are still unsure about your type, your hairdresser or other hair specialists might be able to help.
They may also recommend products that best suit your hair's needs. Remember, the most important thing is to create a routine that works best for you, regardless of the labels we put on our hair.
Want to know which Scandinavian Biolabs product would be the best fit for you? Why not take our Hair Health Quiz to find out in just 2 minutes?
How do I know if my hair is 2C or 3A?
If you are unsure whether your hair is Type 2C or 3A, the direction of growth can be a good indicator. While curly hair expands sideways as it grows, the direction of growth for 2C is more downward.
Can I change my hair type?
Generally speaking, your hair type is not something that can be changed. While it is possible to alter it with chemical treatments, these treatments can be highly damaging. Furthermore, they don’t change the newly growing hairs, so any new growth will be in its natural state. Some other factors, such as hormonal changes or underlying conditions may also have an impact on the texture and shape of your hair.
What is the rarest hair type?
The rarest hair type is 1A. It is pin-straight and doesn't hold any waves or curls.
What is the most fragile hair type?
While it may look robust, Type 4 hair is the most fragile type in general. The lack of natural oils on the length of the hair and its unique structure make it especially prone to dryness and breakage.
Understanding your hair type is key to creating a routine that is tailored to your needs. However, it is important to remember that hair is complex and can be difficult to classify. If you are not sure what your hair type is, don’t worry - the most important thing is to use products that work well for you. By choosing products that are designed to address your hair's specific needs, you can keep your mane healthy, and avoid common issues like breakage and shedding.
The information we provide is not intended to mitigate, prevent, treat, cure or diagnose any disease or condition. If you have any concerns about your health, please consult your doctor.
Mettrie, R., Saint-Léger, D., Loussouarn, G., Garcel, A., Porter, C., & Langaney, A. (2007). Shape Variability and Classification of Human Hair: A Worldwide Approach. Human Biology 79(3), 265-281. doi:10.1353/hub.2007.0045
Moody, S.N., Van Dammen, L., Wang, W., Greder, K.A., Neiderhiser, J.M., Afulani, P.A., Willette, A., Shirtcliff, E.A. (2022) .Impact of hair type, hair sample, weight, external hair exposures, and race on cumulative hair cortisol. Psychoneuroendocrinology. 142, 105805. doi.org/10.1016/j.psyneuen.2022.105805