What Is A Soap Cap And Why Should You Use It?

Have you ever heard of the term, “soap cap”?

If you’re into hair color, you need to know what a soap cap is. Let’s talk about how you can use this awesome technique to your advantage.

There are a few different types of soap caps (also known as shampoo caps, or color balancers). In this post, I’ll explain what they are and how to use them.

If you are a DIY hair colorist, you should probably know how to use a soap cap to your advantage. This professional technique is the perfect way to freshen up your hair color, while doing minimal damage do your hair.

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What You Need to Get Started:

First things, first… you’re gonna need some supplies. Don’t worry, I got you covered.

I also highly recommend you follow up with a deep conditioning treatment to keep your hair happy. I LOVE the It’s a 10 Miracle Deep Conditioner for projects like this.

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1. The “Traditional” Soap Cap with Color

Preparation of hair dye. Isolated on white background

This type of soap cap can be used to refresh dull hair color.

To perform a traditional soap cap: 

  • Mix hair color with equal parts shampoo
  • Apply to the hair and thoroughly saturate
  • Process for 5-10 minutes
  • Rinse, shampoo and style as usual

This method works best if you want to freshen up your color without recoloring your hair.

For example, if you’re just touching up your roots, you can use this method to revive the rest of your hair without the extra damage.

It could also just be used to refresh color between applications. The added shampoo dilutes the color so it won’t darken the previously colored hair.

It also ensures even application, which is a must.


2. Soap Cap with Bleach and Developer

Portrait of beautiful young woman dyeing hairs - isolated on white

I use this soap cap technique reasonably often on my own hair, as it is beneficial for platinum blonde hair. It can also be called a “color balancer” or “bleach bath.”

I use it to freshen up my bleached hair after touching up my roots or even just to freshen up in between applications. It does a lot less damage than re-bleaching the hair over and over again.

You could also use this type of soap cap to lift color gently. For instance, it will take out most semi-permanent colors without doing extensive damage.

You could also try to gently lift darker colors without doing too much damage. The Paul Mitchell color line recommends doing this before any color service (when switching color lines) to create a “fresh canvas” for the new color.

To perform a color balancer, you need to mix equal parts bleach, shampoo, and developer. Like the previous form of soap cap, process for 5-10 minutes, then rinse and deep condition.

3. Soap Cap with Bleach, No Developer

Portrait of young beautiful woman washing her head

I honestly just learned about this type of soap cap yesterday, and it’s pretty much the greatest thing ever. You can mix powdered bleach with shampoo, and it will lift color out of the hair. Skipping on the developer cuts down the damage done to the hair.

Yesterday, my co-worker tried to tone her hair with Redken 8T (Titanium Hair Toner), which is silver for those of you that don’t know. Well…her hair quickly turned silver. We used this method of soap cap to lift the color out of her hair safely.

Scientifically, I am unsure of how the bleach works without peroxide; I think it has to do with the oxygen molecules from the water mixing with the bleach.

Anyways, believe me, it works, and it does very minimal damage.

Now you know…


Your Turn:  Did you enjoy this post? I’ll love you forever if you share it with your friends on your favorite social media website…

Have you ever used a soap cap to freshen up your hair color? Do you have any tips to add for other DIY hair colorists? I’d love to hear your feedback in the comments section below…

RELATED: How To Use A Hair Toner For Brassiness

68 thoughts on “What Is A Soap Cap And Why Should You Use It?”

  1. When using the soap cap with bleach and no developer, how long do you leave that on? still 5-10 minutes, or can you leave a little longer if necessary?

    Reply
  2. I’M planning on doing a bleach soap cap on myself. I bleached my hair about a month ago and the job was uneven and darker in some spots. after bleaching my hair ranged from level 10 – level 8 in different areas. I applied semipermanent color over it anyways that has now faded. my question is: will doing the soap cap lift my hair or just remove the color. the color has faded but is still present on my hair. I am planning on using 30 volume because i want to try to even out the uneven base. thanks so much and i don’t know why this is in all caps.

    Reply
  3. I’m wondering if it’s possible to do the first one (dye and shampoo) with a semi permanent dye like the Manic Panic ones? I’m trying to find a way to refresh red dye without completely dyeing it again.

    Reply
    • The “manic panic” types of COLOURS are direct dyes ( intense depositing colour thats alrEady mixed with a deep conditioner. No lifting or lightening involved) so u wouldN’t need to use for the colour cap technique. To dilute a direct dye colour just add conditioner to the colour. The colour cap is meant to be used with normal hair colour that requires a developer to be mixed with And then the addition of shampoo makes it a colour cap. I hope this helps

      Reply
  4. Helo 🙂
    I love doing soap caps on my dark hair that tends to get brassy. I’m doing one where I apply cocnut oil first to protect. my question is..if i just colored with 30 vol and a light ash blonde all over but my black lower half isn’t lifting is it safe to do a soap cap the next day? thank you for your expertese!!
    jenn

    Reply
    • In case you still need to know, You can do more than one soap cap back to back depending on the health of your hair. I’ve done 3 soap caps back to back before when getting someone from dark to light and it didn’t damage the hair much at all.

      Reply
  5. I used a Redken 9T and a 9P with adding low lights, that turned out to dark, using a 10 volume. for low lights that i wanted more subtle. I am trying to use a gentle soap cap or start with a golden schwartzkoph shampoo or a pureology gold shampoo. my hair is fragile and i am thinning.
    could you please give me some insight on this?

    Reply
    • I am a cosmetologist. It depends on how fragile your haIr is. If its breaking A lot and brittle i would advise against using Bleach aS it wi make It worse. You could Get a hair mask with keratin in it and use it once a weEk to get your hair HeAlthy again and then use a soap cap. You can also use a color remover but its damaging as well.

      Reply
  6. I do not have colored hair. It has naturally turned gray/silver from VERY dark brown. I have several sections which are normally bright white but have discolored into an almost blonde color. I read that using the shampoo cap (with developer) for 5 to 10 minutes will take out the discoloration. But what will happen with the rest of my hair? The parts that aren’t GRAY are lighter, MORE like lIGHT brown now. But it STILL seems DARKER to me at the nape of MY neck. This makes my hair look highlighted with steele GRAY and most people don’t believe me when I say it isn’t colored.

    Reply
    • Have you ever tried using like a purple shampoo to tone out the yellow colors without lightening the dark hair? I’d give that a try first… if not, you can probably soap cap it, but I would only hit the white areas. Hope that helps 🙂

      Reply
    • Hi. I’m a cosmetologist. To get the silver/white back i suggest You use a purple toning shampoo like Matrix So Silver. It will tone out the Yellow. If you used a Soap cap it would Also Lighten the darker parts of your Hair. The purple toning shampoo will only tone the white/silver.

      Reply
  7. I Dyed MY HAIR (TWICE WITHIN A WEEK OF DIFFERENCE EACH) WITH A 11.111 COLOR, MY ROOTS WERE NATURAL aND THEY TURNed OUT PRETTY YELLOW, I WANT TO GET RID OFF IT, BUT I’M SCARED OF RUINING MY HAIR ONCE IT IS NOT SO LONG SINCE I dyeD, SHOULD I WAIT A LITTLE LONGER?

    Reply

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