Wella Welloxon Perfect 12% 40Vol Creme Developer for Professional Colour Activation for Salons & Stylists 500ml/16.91 oz

Forty volume is the strongest developer in the standard range, and choosing it should be deliberate rather than a default. At 12% it delivers maximum lift, up to four or five levels, which is what high-lift blonde work needs and what a root touch-up very much does not.

Welloxon Perfect is Wella's own oxidant, formulated to pair with their colour lines. The consistency is creme rather than liquid, so it holds on the section during mixing and application instead of running down the hair and off the foil. Even saturation is most of the battle with high lift, because a runny mix processes at different speeds from root to end and leaves you correcting bands afterwards.

It also carries enough power for solid grey coverage where the colour line calls for a stronger developer, and the 500ml (16.91 oz) bottle is the salon size rather than the one-service size.

Mix to the ratio the colour line specifies, and take a strand test first. Forty volume on hair that has already been lightened is where damage happens, so match the developer to the condition of the hair in front of you rather than to the shade on the swatch.

Keep it capped and out of sunlight. Peroxide weakens once a bottle has been open a while, and that is a common reason a lift comes up short.