In order for your hair color to do its job (make you look fabulous) it has to be mixed with a developer. Hair color developers use hydrogen peroxide to activate hair color and allow it to open up the hair’s cuticle and deposit the color deep into the hair strand. Different developers exist because they are different strengths (this is determined by the amount of peroxide). The strength of the developer determines how light or dark your hair color can be. It is very important to pick the correct developer in order to achieve the results you want. Developers range from 10 volume up to 40 volume and each one has a specific purpose!
10 Volume (3% peroxide) – When You Want to Go Darker or Stay the Same
10 volume is for depositing color only. It will not give you any lift so you will not get any lighter when you use it. Instead you would choose 10 volume when you are going from a lighter to a darker shade or when you want to refresh your color with the same shade that you are currently. Keep in mind that 10 volume will not give you full gray coverage but can provide gray blending when going darker (a great option if you want to camouflage grays and keep hair color low maintenance). 10 volume is also used with demi permanent hair color and toners.
20 Volume (6% peroxide) – Your Go to Developer
20 volume is the most widely used developer. 20 volume gives 1-2 levels of lift, so for example if you’re naturally a level 6 (lightest brown) and want to lighten up to a level 7 (dark blonde) or a level 8 (medium blonde), you would choose 20 volume. You can also use 20 volume to stay the same color that you are currently, especially if you have more than 50% gray hair as it allows for 100% gray coverage.
30 Volume (9% peroxide) – You Need More Lift
30 volume will give you three levels of lift. If you are naturally a level 4 (dark brown) and want to be a level 7 (dark blonde), your good old 20 volume isn’t going to cut it and you’ll definitely going to need to bump up to 30 volume. 30 volume is powerful but still safe to put on your scalp when mixed with color (not bleach!). It is also often mixed with lighteners for balayage and highlighting techniques.
40 Volume (12% peroxide) – You Need a Lot of Lift
40 Volume can give you anywhere from 4-8 levels of lift BUT you cannot put 40 volume on your scalp (ouch!). It is only used for lightening hair in foils or in balayage techniques. You can mix it with powder bleach, cream bleach or color as long as it’s not coming into contact with your skin. If not applied properly and taken off the hair when it’s ready, 40 volume can do a lot of damage to your hair so be sure to leave this one to the professionals!