Hydrogen peroxide, also known as dihydrogen dioxide, has a pH level anywhere from 1 to 5, depending on the solution's concentration and how it is produced. Many hydrogen peroxide solutions contain stabilizers that affect the product's pH. The solution's pH level can be increased or decreased depending on the exact stabilizer that is used.
Stabilizers that are alkaline make the solution more basic, thus increasing the pH level. The stabilizers that are acidic decrease the pH level and cause the hydrogen peroxide to become more acidic. Dihydrogen dioxide products that are pure with few stabilizers generally have a pH between 1 and 4, while products heavily diluted have a pH level from 4 to 5.