How To Test the pH of Soap

The pH or "potential of hydrogen" is the index used to test the level of acidity, neutrality or alkalinity of a solution. It is important to test the pH of soap to know if it is already possible to use it. In this post we will see how to test the pH of soap at home in a simple way. At the end of the post you can also watch our educational video on how to do this test step by step.

If you like to make natural soap at home, you might also like our posts Olive Oil Soap: How to Make It and Its Benefits, Coconut Soap for the Skin: Benefits and How to Make It, and Coconut Soap for Garden and Orchard Pests.

Now let's learn more about the pH.

The pH Values

The pH can vary between the values 0 and 14. The closer to 0, the more acidic. The closer to 14, the more alkaline.

The pH 7 is considered neutral.

The ideal pH of a soap should range between 8 and 10 so that it can gently cleanse the skin.

Source: Freepik

The Test

Let's look at two methods of testing the pH using test strips.

Warning!

• This task should be done with gloves to protect the skin if the soap is not yet cured.
• The pH should be tested during the curing process in order to know if the soap still needs to cure for longer.

Materials Needed

• 1 Kitchen knife
• 1 Cup or bowl of hot water
• 1 Spoon 
• pH test strips

Method 1

1. Cut the soap roughly in half.
2. Remove a bit of the inside.
3. Dissolve the slices in a cup of hot water.
4. Place the strip in the water and test the pH using the color chart on the strip package.

Method 2

1. Wet and rub the soap in hot water.
2. Place the strip over the wet soap.
3. Test the pH using the color chart on the strip package.

Although the first method gives more accurate results, this second method can be used if you do not want to cut the soap.

If the soap is not yet within the normal values (8 - 10), it should be left to cure for some more time, repeating the pH test again.

Here is our step by step video of both methods!

VIDEO - How To Test the pH of Soap