Liquid soap typically has a pH level between 9 and 10.5, which is considered slightly alkaline. This is slightly above neutral pH level, which is 7. While liquid soaps are generally milder than bar soaps, they still have a higher pH than the skin's natural pH level, which is around 4.5 to 5.5. This difference in pH can disrupt the skin's acid mantle, which is responsible for protecting it from harmful bacteria and environmental stressors.