Last updated: August 23, 2021

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Welcome to our hair soap test 2021. Here we present all the hair soaps we have tested. We have compiled detailed background information and added a summary of customer reviews on the web.

We would like to make your purchase decision easier and help you find the best hair soap for you.

You will also find answers to frequently asked questions in our guide. If available, we also offer interesting test videos. Furthermore, you will also find some important information on this page that you should be aware of if you want to buy a hair soap.




Summary

  • Hair soap is the natural, often gentler alternative to conventional shampoo
  • A basic distinction is made between hair soap and solid shampoo
  • Which hair soap is right for you depends on your skin and hair type

The Best Hair Soap: Our Picks

Guide: Questions you should ask yourself before buying a hair soap

What is a hair soap?

Hair soaps are a cleanser for the hair, making them the next great alternative to a hair shampoo. The natural soaps condition the hair and thoroughly cleanse the scalp.

Many conventional hair shampoos irritate and degrease the scalp with harmful substances that can cause extreme dryness and itching. (Image source: unsplash.com / Element5 Digital)

What makes hair soap special is that it contains few harmful substances such as surfactants or silicones. These ingredients can be extremely irritating to the scalp. In addition, hair soaps consist of fewer irritating fats compared to conventional hair products.

In general, it can be said that hair soaps are very mild in composition and thus support the preservation of the hair's own fat and moisture.

Who is hair soap suitable for?

Basically, all skin types and hair types can use hair soap. Whether you have healthy, dry or oily hair - the natural-based soaps care for everything. So you don't have to worry about damaging your hair structure or scalp.

There are no limits to the age or gender of this care product. Nevertheless, parents should use an extra mild hair soap for younger children because of their sensitive scalps.

How much do hair soaps cost?

As with many care products, the price of hair soaps varies depending on how they are made and the ingredients used. The more elaborate the production of the soap and the richer the mixture of substances, the higher the price can be.

Cheap hair soaps can be found for less than 10 euros. If the price is very low, you should pay closer attention to whether the product contains enough nourishing ingredients. In the worst case, manufacturers will not use moisturising substances and will use harmful oils.

The price for mid-range hair soaps is around 10-30 euros. They are often more productive than the cheaper version and are handmade. The cleansing power and skin compatibility of these hair soaps can also be higher.

The brand manufacturers of more expensive hair soaps pay particular attention to the natural production and strong effect of the substances. Many of these soaps are even suitable for allergy sufferers and can reduce hair loss. The price ranges from 30-50 euros.

What alternatives are there to hair soap?

There are many different ways to clean and care for your hair and scalp. Again, it depends on what your skin and hair are sensitive to. The first alternative is to use a conventional shampoo.

They are available in many different varieties and can be bought cheaply. However, in most guidebooks you will read rather negative things about this form of hair washing. The simple production of hair shampoos deprives them of important nutrients.

If you want to be a little creative, you can have fun making your own hair care product. DIY versions with honey, coconut oil and many other substances can be found on the internet.

Here is an example video with instructions for a homemade hair shampoo:

Decision: What types of hair soaps are there and which is the right one for you?

Before we delve deeper into the different criteria for buying a hair soap, we will show you the basic types you should distinguish between:

  • Hair soap
  • Solid shampoo

Most people do not know exactly what these two types of products are. For this very reason, we would like to give you a rough overview in the following.

What are the characteristics of a hair soap and what are the advantages and disadvantages?

The strained soap counteracts itchy and dry scalp and can lead to more volume and manageability of the hair. The hair is gently and carefully cared for on a natural basis.

Advantages
  • Helps irritated scalp
  • More volume and grip
  • Compatible natural product
  • Packaging-free
Disadvantages
  • Residues with hard water
  • Difficult hair washing
  • Higher price
  • Long habituation phase

On the other hand, hair soaps also bring some complications. When hair is washed with hard water, hair soaps can leave strands and residue.

What are the characteristics of a solid shampoo and what are the advantages and disadvantages?

Solid shampoo has the same form as a hair soap, but contains more of the same ingredients as the traditional liquid shampoo.

With solid shampoo, there are no problems with hair residue due to chalky water because of the different mixture. In addition, milder surfactants are usually used in the production process and the shampoo is offered without packaging.

Advantages
  • No hair residue
  • Lathers well
  • Mild surfactants
  • Packaging-free
Disadvantages
  • Harmful ingredients
  • Troublesome hair washing
  • Higher price
  • Often not a natural product

Although some try to avoid it, many solid shampoos contain harmful ingredients such as SLS or SLES. Again, shampooing is rather laborious and a slightly higher price is to be expected.

Since hair soaps and solid hair shampoos differ mainly in their substances, most people base their decision on the hardness of their water. You should find out the hardness of your water from your city council.

Buying criteria: You can use these factors to compare and evaluate hair soaps

In the following, we will show you which factors you can use to decide which hair soap is right for you.

The following overview shows comprehensive buying criteria that you should use as a guide:

  • Hair type
  • Skin type
  • Ingredients
  • Degree of superfatness of a hair soap
  • Hardness of water
  • Vegan

Hair type

Hair - we all have it, some long and some short. Some in blond, others in brown. In fact, these factors are rather irrelevant for hair soap care. When it comes to hair type, we categorise a little differently here:

  • thin hair
  • thick hair
  • straight hair
  • curly hair
  • dry hair

Thin hair

Thin hair is often prone to split ends and dryness due to its easily damaged structure. You will find suitable oils in hair soaps for damaged hair with a thin structure in the chapter on ingredients.

Thick hair

Thick hair can also suffer from dryness due to the wrong care, especially because it often tangles faster and is difficult to tame. However, many people also complain about an oily scalp.

Straight hair

This type of hair structure is usually very vulnerable and turns out significantly thinner. Straight hair often lacks volume and grip, and a suitable hair soap can be a real saviour.

Curly hair

Most people with curly hair have a thicker and firmer hair structure. For this very reason, they are often not easy to comb and difficult to get soft.

As you can see, different hair types have different starting points, but most have one thing in common: greasy roots and dry ends.

Hair soaps come in many different types, so you should read up on the different types and criteria before buying. (Image source: unsplash.com / Heather Ford)

Skin type

Washing your hair is certainly not only related to your hair, but also to what the hair care product comes into contact with: our scalp. It is this - and not our hair - that is responsible for an oily or flaky scalp.

Dry scalp

Anyone who has a dry scalp is more or less familiar with dandruff and constant itching. This is a sign that the hair care product was not gentle enough for the skin on your head. Hair soap with a higher superfatness level can help a lot.

Oily scalp

If you have an oily scalp, it's the other way around. The scalp is degreased by conventional hair cleansers and thus quickly becomes greasy again. Re-greasing hair soaps can reduce the oily scalp. In contrast to the dry scalp, a rather low degree of overgreasing of the soap should be selected.

Ingredients

Once you have roughly categorised your hair type and scalp type, let's now take a look at the appropriate properties of hair soaps.

As a general rule, you can say which ingredients are good for your hair and which you should steer clear of. We have put together two tables that you can quickly compare with different hair soaps.

Good ingredients

Substances Effect
Avocado oil Cares for hair, Lathers
Olive oil Cares for hair
Babassu oil/butter Cares for hair, Lathers
Castor oil Cares for scalp, Reduces hair loss
Butter (Shea, Mango, Cocoa) Helps dry hair
Beer Strengthens hair, Adds shine
Egg Adds protein, Adds shine
Aloe Vera Moisturises
Essential oils Nice scent, Nourishes scalp

Bad ingredients

Substances Effect
Palm oil Sticky, stringy hair
Coconut oil Dries out hair
Glycerin Dries out hair, Drains moisture
Dyes Allergenic, Irritates skin
Synthetic fragrances Hormone-like effect, Allergenic, Irritates skin

Basically, it is difficult to determine which substances give your hair the desired effect. Different substances in hair soaps have different effects on different people. Don't necessarily just listen to the advice of others, but try it out for yourself.

Only natural soaps are really healthy soaps. Avoid chemically produced substances as much as possible and only rely on certified quality seals.

Oversaturation level of a hair soap

Our hair is often washed nowadays, because a greasy or dry cut is not considered healthy, nor beautiful. Unfortunately, we are often responsible for these problems ourselves. Through frequent cleaning, we dry out our scalp, whereupon it produces all the more sebum (grease).

The drier the hair, the higher the level of oil in your hair soap should be. If you feel that your roots are still greasy quickly, then you should increase the grease level further.

While conventional hair cleansers imbalance the moisture and oil balance of the skin, hair soaps can care for the scalp with moisturising substances. The scalp is not degreased and therefore does not have to become greasy again immediately - not bad, right?

Degree of overgreasing Percentage
Low Under 4%
Medium 4-6%
High Over 6%

Water hardness

If you have very soft water at home, you should have no problems with hair soap. Your product would not form a calcareous bond with the water.

If the water is medium hard, i.e. a little hard, you might notice some residue in your hair. An "acid rinse" would be advantageous here. You can find out exactly what this is in the trivia at the end of the article.

If you have very hard water, you will have the most problems washing your hair with hair soap. If this is the case for you, you can find out about a lime-absorbing shower head or make an acid rinse after every hair wash.

Vegan

Vegan products are becoming increasingly popular - they can be good for the environment as well as your health. You would recognise a vegan hair soap by the fact that it is only based on natural substances and does not use any animal ingredients.

A vegan hair soap does not use animal testing or substances that animals have produced. This includes, for example, goat's milk, sheep's milk or beeswax. Instead, they are mostly made from vegetable oils and have been organically grown.

Facts worth knowing about hair soap

How do you use hair soap correctly?

Because hair soap is a little more difficult to use due to its solid form and foams differently, some people despair when it comes to the question of how to use it correctly. In the following, we show you how to do it:

  1. Wet hair and hair soap
  2. Rub soap onto the head, re-moisten if necessary
  3. Rub the hair soap between your hands until it is creamy and foamy and massage it into the scalp for about 30 seconds
  4. Massage the remaining foam into the lengths of the hair
  5. Rinse the scalp and hair thoroughly with warm water
  6. Rinse scalp and hair briefly with cool water
  7. Check for residual soap in the hair, repeat steps 5 and 6 several times if necessary

When you use hair soap for the first time, you will notice that it takes a little longer to wash out than liquid shampoos. Also, many people say that their hair needs 3-4 washes to get used to the new product.

Despite their solid consistency, many hair soaps lather and apply just as well as liquid shampoos. (Image source: unsplash.com / Matthew Tkocz)

Conditioning after washing - conditioner and acid rinse

If you feel the need to condition your hair after washing it with soap, here are two different ways to do it:

  • Acid rinse
  • Conditioner

Acid rinse

As mentioned earlier, very chalky water combined with soap can leave a residue in your hair. To remove the lime and make your hair smooth and manageable again, you can use an acid rinse.

You can make your own acid rinse using a litre of water and a few tablespoons of vinegar or lemon juice. The mixture is applied to the hair and scalp after shampooing and left to work for a while. Some leave it on completely, others rinse it out after 15 minutes. Try out what works better for your hair.

Conditioner

Another alternative for conditioning your hair after shampooing is to use a conditioner. Conditioners are usually simple conditioners that soften and shine the hair.

The conditioner can be used on the hair as well as on the scalp. Depending on the package label, the product should be left on for a few minutes and the hair rinsed again with water.

Image source: 123rf.com / didecs

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