According to the University of California Santa Barbara, the pH of rubbing alcohol is about 5.5. This level can vary based on the dilution factor or the brand of the rubbing alcohol.
The pH scale measures how acidic or basic (alkaline) a substance is. The pH scale ranges from 0, or very acidic, to 14, or very basic. For example, battery acid has a pH level of about 1, while lye has a pH of about 13. Substances with a pH of 7 are neutral, making rubbing alcohol mildly acidic. This pH level is similar to the typical pH range of precipitation.