PH is a scientific measurement that indicates how acidic, alkaline, or neutral an environment or product is. It is indicated on a scale of 0-14. 0-7 on the scale indicates something which is acidic. A PH of 7 indicates that something is neutral, while a PH of 7-14 indicates that something is alkaline. Our haircare products, including shampoo, have a PH level, although it is best to select a product marked as PH balanced as this is best for your scalp and your hair.