Wella developer guide: volumes (6%, 9%, 12%) and mixing ratios

Which Welloxon Perfect volume for which job, and the typical mixing ratios for Koleston, Illumina, Color Touch and Blondor.

How-to5 June 20267 min read

Developer (peroxide) is what activates colour and controls lift. As a rule of thumb: 6% (20 vol) for grey coverage and 1–2 levels of lift, 9% (30 vol) for 2–3 levels, and 12% (40 vol) for high-lift. Match the volume to the lift you need — no more.

The short answer

  • 1.9% ≈ 6 vol and 4% ≈ 13 vol: tone/deposit, minimal lift.
  • 6% ≈ 20 vol: grey coverage and 1–2 levels of lift (the workhorse).
  • 9% ≈ 30 vol: 2–3 levels of lift.
  • 12% ≈ 40 vol: maximum lift / high-lift blondes.
  • Always confirm ratios and volumes against the current pack and strand test.

What the volumes do

Developer volume sets how much the cuticle opens and how much lift you get. Lower volumes mainly deposit tone and cover grey with minimal lightening; higher volumes lift the natural pigment further so a lighter target can show through. The principle is simple: use the lowest volume that achieves your result, because excess developer means unnecessary stress on the hair without a better outcome.

Typical mixing ratios

  • Koleston Perfect — usually 1:1 with Welloxon Perfect (e.g. 60g : 60ml).
  • Koleston Perfect Special Blonde 12/ — usually 1:2.
  • Illumina Color — usually 1:1.
  • Color Touch — usually 1:2 with Color Touch Emulsion (1.9% or 4%).
  • Blondor lightening powder — usually 1:1.5 to 1:2 with developer.
  • Shinefinity — 1:1 with its zero-lift activator.

Ratios are quoted by weight/volume and vary by shade family and the result you’re after, so always treat these as a starting point and confirm against the current instructions for your exact product.

Common mistakes

  • Reaching for 40 vol when 20 would cover the grey — more lift than needed, more damage.
  • Guessing the ratio instead of weighing — inconsistent saturation and patchy results.
  • Skipping the strand test on a new base or a correction.
  • Storing mixed colour — once mixed it’s working, so use it fresh.
This is general guidance for trained professionals, not a substitute for Wella’s current instructions. Mixing ratios, developer volumes and timings vary by product and market and change over time — always follow the directions in the pack, carry out the required allergy/skin-allergy test 48 hours before, and do a strand test.

Quick questions

Is 20 volume the same as 6%?
Yes — roughly. 6% peroxide is about 20 volume, 9% is about 30 volume and 12% is about 40 volume. Wella developers are labelled by percentage.
What volume covers grey?
6% (20 vol) is the usual choice for solid grey coverage with permanent colour; resistant grey may need a tweak to the formula rather than a higher volume — follow the pack.

Wella, Koleston Perfect, Illumina Color, Color Touch, Shinefinity, Blondor and Color Fresh are trademarks of their respective owner. Hair Colour Supplies is an independent stockist, not affiliated with or endorsed by Wella. On-screen colours are indicative only.

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