Blue vs. Purple Shampoo: How to Choose

Preserving your hair color at home is a must — especially if you bleach or lighten it. Chemically lightened strands oxidize and change over time, undoubtedly showing unwanted yellow, red, or orange tones at some point. This is known as brassiness and everything from fading to everyday styling, pollution and minerals in the water cause it, making it impossible to avoid. The only way to get rid of brassiness is to tone it. Enter blue and purple shampoo. Both of these are used to tone brassiness, by depositing colored pigments into the hair. So what’s the difference and which toning shampoo should you use? We’re sharing everything you need to know about blue vs. purple shampoo ahead!

Purple shampoo is a shampoo that contains purple pigment to neutralize yellow tones on lighter hair. So how does purple shampoo work? The answer to this lies in the color wheel — a tool used in color theory to understand the relationships between individual colors. Colors opposite each other on the color wheel are called complementary, and are as different from each other as possible. Combining complementary colors cancels them out. Purple sits directly across from yellow on the color wheel. So depositing purple pigments on brassy, yellow tones color-corrects the hue, restoring it to a brighter cooler tone. Your strands can benefit from a purple shampoo if you:

• Have blonde hair or gray hair
• Are brunette with highlights, ombre, balayage, foil, or a money piece
• Want to neutralize unwanted brassy yellow shades by cooling warm tones

Blue shampoo contains blue pigments that are deposited into the hair when you shampoo. Like purple shampoo, it neutralizes the brassy tones that occur when hair is lightened. But where lighter hair color has underlying yellow tones when lifted, darker hair color has underlying orange tones. Orange is opposite blue on the color wheel. This means blue cancels out orange. If you’ve got dark hair with balayage, ombré or conventional highlights, if you’ve lightened your dark hair completely, or if you have a combination of dark and light hair with highlights, blue shampoo is your solution for brassiness. So what does blue shampoo do? Blue shampoo:

• Neutralizes unwanted orange, red and copper tones that shows up in lightened hair
• Keeps brunette hair looking vibrant and multi-dimensional
• Uses blue pigments to cool down warm tones

Purple shampoo uses purple pigments to neutralize yellow tones and keeps blondes brighter and ashier. Purple shampoo is also great for silver/white hair as well. Blue shampoo uses blue pigments to neutralize brassy orange tones in the hair. Essentially, purple shampoo and blue shampoo work on yellow tones and orange tones, respectively. If you look at a color wheel, you see that blue is directly across from the orange tones and purple is directly across from the yellow tones. Purple cancels out yellow and blue cancels out orange.

As lighter hair loses pigment through the chemical process of lightning, it tends to lift yellow, where darker hair loses pigment and lifts orange. But the undertones that appear in your hair will help you determine whether you should try blue vs. purple shampoo. If you have brassy orange or even red tones, blue shampoo is your best bet. However, blue pigment won’t help with yellow undertones. The reverse is true for yellow undertones. Purple shampoo is great for removing yellowness, but not effective for orange or red tones. While you should stick with purple or blue shampoo most of the time, you do have the option to use both if you have multiple undertones. But a good rule of thumb is that a blue shampoo is best for dark hair and brunettes; and purple shampoo is better for blondes, silver or gray hair. 

They sure do! Blue and purple shampoos work by coating the hair shaft, canceling out brassiness, and adding shine. The tone-correcting pigments help protect color from fading, in addition to promoting healthy hair, boosting shine, enhancing vibrancy and reducing frizz. Even hair that hasn’t been chemically lightened can benefit from a blue or purple shampoo every once in a while. Sun exposure, everyday styling, even pollution can turn your brunette or blonde brassy. Blue and purple shampoos can subtly tone down unwanted warm shades to cooler, brighter hues.

A blue or purple shampoo won't fully replace your everyday shampoo. You’ll swap it in every few washes. How often you do is entirely up to you. We recommend starting with once every week or two, then building up as needed. Always use blue or purple shampoo on wet hair. Don’t apply it on dry because the hair is more porous and it will grab too much of the blue or purple pigment. Lather it up in your hands and work it into your scalp, using gentle circular motions work the shampoo between strands, and down the shaft. Leave it on for two to four minutes depending on the amount of brassiness in the hair, and use cool water when rinsing, to close the cuticle and seal the color. Always follow with a conditioner for colored hair. If you start to notice a purple or blue tone in your hair, you’re using it too often. Opt for a clarifying shampoo to remove the tone and keep your blue or purple shampoo routine to once a week or less.
 

Regardless of which color toning shampoo you choose, remember that the key to keeping your color treated strands vibrant is lots of moisture. Use only high quality, color-safe styling products and hair masks and check out more of our hair care tips for color-treated hair. All Davines are free of harmful toxins, use natural ingredients, and are made with renewable energy and packaging that minimizes the environmental impact. Our hair care isn’t just good for your hair, it’s good for the planet.

by Jaclyn LaBadia, featured contributor