Soaps are slightly basic because they are the salts of strong bases and weak acids. If a soap is too basic, it can harm the skin, the surfaces it's supposed to clean, and the clothes it's supposed to clean. Note : A base is a chemical that takes hydrogen ions while an acid donates hydrogen ions.

Why is soap a base?

Soap is a basic salt that is made by the reaction of long-chain fatty acids such as carboxylic acid(weak acid) with a strong base like sodium hydroxide(NaOH) or potassium hydroxide(KOH). The majority of soaps have a pH value within the range of 9-10 which shows their slightly basic nature in solution.

Is soap considered basic?

If you're not sure if what you have is a soap or a detergent, give it a test with a pH strip - detergents are neutral or acidic, whereas soap is always basic.