Conditioner is typically a base. The pH of most conditioners ranges from 3.5 to 5.5, which is slightly acidic. However, some conditioners may have a pH closer to 7, which is neutral. The reason why conditioners are typically acidic is because hair has a natural pH of around 4.5 to 5.5. When the hair is exposed to an alkaline solution, such as soap, the pH of the hair can be raised, causing the hair to become dry and brittle. Conditioners help to restore the hair's natural pH balance and can also help to repair damaged hair.