Blue shampoo is a color-correcting shampoo that deposits blue pigments onto your hair to neutralize brassy orange and red tones, especially in brunette and some blonde hair.

What blue shampoo actually does

  • Neutralizes warm orange, red, and copper tones that make brown hair look brassy or “rusty.”
  • Keeps brunette hair looking cooler, more ashy, and multi-dimensional instead of warm and dull.
  • Helps some blondes (especially darker or highlighted blondes) tone down orangey brass after lightening.
  • Gently tones by depositing blue pigment on the hair surface; it doesn’t permanently dye hair blue.
  • Can revive vibrancy, gloss, and shine in color-treated hair that’s been faded by sun, chlorine, or salt water.

Think of it as a toner in shampoo form: blue cancels orange on the color wheel, so the blue pigments visually balance out those warm undertones.

Who should use blue shampoo

  • Brunettes (natural or dyed) who see orange or red brassiness in their hair.
  • Brown hair with balayage, ombrĂŠ, or highlights that are starting to look too warm or coppery.
  • Dark blondes or blonde hair that pulls more orange than yellow after lightening.

If your hair is very light, pale blonde and goes yellow (not orange), purple shampoo is usually a better match than blue.

Blue vs purple shampoo (quick view)

[5][7][3] [8][3][5] [1][3][5] [5][8] [7][1][5] [8][5]
Feature Blue Shampoo Purple Shampoo
Target hair color Brunettes, dark blondes, brown hair with highlights Blondes, very light or platinum hair, some highlighted brunettes
Neutralizes Orange, red, copper tones Yellow tones
Effect Makes brown hair cooler, ashy, richer Makes blonde hair cooler, icy, less “yellow”

How to use blue shampoo (without wrecking your hair)

Most brands suggest using blue shampoo occasionally, not every wash, so you don’t over-tone or dry out your hair.

  1. Wet hair thoroughly, then apply a small amount (dime-sized for short hair, quarter-sized for long hair).
  1. Focus on the brassiest areas (often mids and ends), then work through the rest of your hair.
  1. Let it sit for the time on the bottle—typically a couple of minutes—then rinse well.
  1. Follow with a hydrating conditioner or mask to keep hair soft.
  1. Use it weekly or as needed depending on how fast brassiness shows up.

If you leave it on too long or use it too often, hair can look slightly over- toned or dull, but this usually fades after a few regular washes.

Little story-style example

Imagine you dyed your naturally dark brown hair a cooler, espresso shade. It looks amazing for the first couple of weeks, then sunlight and hot showers slowly pull warm pigments through and your hair drifts toward orangey-brown. You swap your regular shampoo for blue shampoo once a week: after the third or fourth use, that loud orange cast softens, and your color looks closer to that original cool brunette again—without another salon appointment.

Bottom note: Information gathered from public forums or data available on the internet and portrayed here.