Which developer is most commonly used with permanent hair color?

• A. 10-volume hydrogen peroxide
• B. 20-volume hydrogen peroxide
• C. 30-volume hydrogen peroxide
• D. 40-volume hydrogen peroxide

Answer: (B)

The main idea is how the strength of the developer affects color processing, and which strength is typically used with permanent color. Hydrogen peroxide in the developer activates the dye and opens the hair cuticle so pigment can enter the cortex. For most permanent color formulas, a 20-volume peroxide (about 6%) is the standard because it provides a reliable balance of lift and deposit while keeping damage manageable. It typically lifts the hair about 1–2 levels, which covers common color changes without over-processing.

Lower strength, like 10-volume, offers minimal lift and is mainly used for deposit-only applications or tonal glosses on pre-lightened hair. Higher strengths, 30- or 40-volume, deliver more lift but are harsher on the hair and are used only for specific high-lift blonding or dramatic color changes with careful formulation and timing. So, 20-volume is the most commonly used choice with permanent hair color.