Hair Toning Basics
Toners can neutralise unwanted yellow, orange or brassy shades from your hair. Toning hair is not difficult, if you know the basics.
Keep in mind that toners can only neutralise unwanted shades from your hair, but they alone do NOT lighten your hair. If you want to achieve a shade lighter than your current hair colour, you will need to bleach you hair to the desired level first.
Pick the right toner or colour for your hair
The following chart shows hair colour levels, the underlaying pigment (undertone), as well as the neutralising tone. The neutralising tone is the shade of the toner or colour that will remove the unwanted underlying tone from your hair.
Determine what level you currently are and make sure it is light enough for the colour you would like to achieve.
If you have dark blonde hair and you would like to go platinum blonde, you would have to pre-lighten (bleach) your hair to a very pale yellow (level 10) first. Then you can use a violet-based toner, such as Wella Color Charm T18 LIGHTEST ASH BLONDE, to cancel out the unwanted yellow tones. The result is a neutral, almost white blonde.
Your hair level is currently a level 6 brassy dark blonde and you would just like to remove some of the unwanted warm shades, without lightening your hair. The underlying pigment would be orange. To neutralise the brassy shade, you could use Wella Color Charm 7A/672 MEDIUM SMOKEY ASH BLONDE or Wella Color Charm 6A/462 DARK ASH BLONDE, for example. They are both blue-based and counteract the oranges in your hair, leaving you with a more neutral dark blonde shade.