What Developer Do I Use With Bleach? Get The Right Strength.

Whether you’re a novice or experienced hairstylist, the one question that comes up most often is – what developer do I use with bleach?

It can be mind boggling trying to find the right type of developer or volume level for your hair, but don’t worry – we’ve got you covered! 

We’re here to go over all things ‘bleach and developer’ and provide tips on how to choose the best option for your individual situation.

From understanding peroxide levels and creamy consistencies, to working out liquid volume levels; by the end of this article you will have everything you need in order to confidently select the ideal product combination.

So let’s find you the perfect balance between dye and lightening agent. 

What is developer and what does it do? 

Hair developer is a creamy solution that’s used to activate hair dye or bleach and help it penetrate your hair strands.

It works by opening up the hair cuticle so that the color molecules can get inside and work their magic.

Depending on the strength of the developer and the type of dye you’re using, you can achieve anything from a subtle change to a bold new look. 

Think of the developer as the key player that helps unlock the door to your new hair color. Without it, the bleach or hair dye wouldn’t be effective.

what does developer do to hair infographic - alkaline hydrogen peroxide causes the hair cuticle to lift and open. Hair color or bleach pigments travel under the cuticle to the hair cortext

What are developer volumes?

Developers come in different levels, generally ranging from 10 to 40.

But what do these numbers imply, and how do you know which one is right for you? Let’s break it down: 

  • 10 Volume Developer (3% peroxide) is great for anyone who wants a slight color lift. It’s perfect if your desired hair color is no more than one shade lighter than your current color.
  • 20 Volume Developer (6% peroxide) is the most common level and works for most people. It’s ideal if you want to go 1-2 shades lighter.
  • 30 Volume Developer (9% peroxide) is used for a moderate color lift. This is the one to choose if you’re aiming for 2-3 shades lighter.
  • 40 Volume Developer (12% peroxide) is designed for a significant color change. It’s the strongest developer and will lift your hair color 3-4 shades lighter.

But remember, the higher the volume, the more damage it can potentially do to your hair. So, always err on the side of caution and start with a lower volume if you’re unsure. 

what developer do i need with bleach

What developer do I use with bleach?

Deciding the right volume developer for your hair can feel like a tricky science experiment.

But don’t worry! Here’s what you need to know:

The Basics 

Developer, in the world of hair coloring, is a hydrogen peroxide-based product that’s absolutely vital in the process of hair coloring.

It’s what helps open up the hair cuticle, allowing the color to penetrate and do its work. 

Volume Levels 

Developers come in different volumes, usually ranging from 10 to 40. The volume you choose depends mainly on two things: 

  • The natural color of your hair.
  • How much you want to lighten it.
what developer do i use with bleach infographic table - Developer VolumeFunction10 VolumeFor going darker or same level color change with minimal lift.20 VolumeFor going 1-2 levels lighter, or covering grey hair.30 VolumeFor going 2-3 levels lighter.40 VolumeFor going 3-4 levels lighter.

Note: The higher the volume, the more it’ll lighten your hair, but it also means more damage. So, proceed with caution!

How to Choose the Right Volume 

Still not sure which volume to go for? Here are a couple of pointers: 

  1. If you’re going for a subtle change or just want to cover some grays, a 10 or 20 volume developer should do the trick.
  2. If you’re going for a dramatic change, like going from brunette to blonde, you might need a 30 or 40 volume developer

Just remember, the higher the volume, the more damaging it can be for your hair.

What is the right ratio of bleach to developer?

When it comes to hair bleaching, getting the right ratio of bleach to developer is critical for achieving the desired results. But what is the ‘right’ ratio?? 

Well, typically, the ratio is 1:2, meaning for every one part of bleach powder, you should use two parts of developer.

However, this ratio isn’t set in stone and can vary based on your hair type and desired level of lightening. Here’s how:

The 1:2 Ratio 

The 1:2 ratio is a standard rule of thumb in the hair bleaching world.

It provides a consistency that’s easy to apply, while also ensuring enough developer is present to activate the bleach. Here’s how it works: 

  • One Part Bleach: Bleach opens the hair cuticle to allow the developer to penetrate.
  • Two Parts Developer: The developer oxidizes the bleach, allowing it to decolorize the pigment in your hair.

When to Vary the Ratio 

While the 1:2 ratio generally works well, there may be instances where you might need to tweak it a bit. For example: 

  • If your hair is fine or damaged, you might want to use less developer to avoid further damage.
  • If you’re aiming for a subtle lightening, a lower developer volume might suffice.

Still, it’s always best to consult with a professional or follow the manufacturer’s instructions on the bleach and developer kit packaging

Note: Always perform a strand test before applying the mixture to your entire head. This will give you an idea of how your hair will react to the bleach and developer mix.

How to Mix Bleach and Developer 

  1. Measure out the bleach powder and developer according to your preferred ratio.
  2. Mix them together in a non-metallic bowl until you get a yogurt-like consistency, ensuring all the lumps are gone.
  3. Once mixed, apply promptly to your hair as the potency of the mixture decreases with time.

While the right ratio of bleach to developer is typically 1:2, this can vary depending on your individual hair type and lightening goals.

So, always proceed with caution and when in doubt, seek professional advice!

Watch and learn: How to mix bleach and developer

Here’s a great video tutorial that shows you how to get the right voluem of developer for you, how to mix it with bleach powder nad which brands work the best!

How to use developer when bleaching.

Preparing your Hair for Bleach 

Before using the developer, it’s important to prepare your hair by washing it with a clarifying shampoo to remove any product buildup or oils. This will help the bleach to penetrate evenly. 

Gathering the Necessary Supplies 

Next, gather all the necessary supplies:

  • A non-metal mixing bowl
  • A brush or applicator
  • Gloves
  • A timer.
  • An old towel or cape to protect your clothing. 

Mixing and Applying the Developer 

To mix the developer, follow the instructions provided on the packaging.

Typically, you’ll need to mix equal parts of developer and bleach powder. Use the brush or applicator to stir the mixture until it reaches a smooth and creamy consistency. 

Once the mixture is ready, put on your gloves to protect your hands from the chemicals.

Begin applying the bleach to your hair, starting from the ends and working your way up to the roots. Make sure to saturate each section thoroughly for even results. 

Monitoring the Bleaching Process 

As you apply the bleach, it’s important to keep track of the time!

Different hair types and desired levels of lightness require different processing times. Refer to the instructions on the bleach powder or developer to determine the recommended time. 

While the bleach is processing, it’s crucial to monitor your hair’s condition.

Check the color and texture regularly to ensure it’s lightening evenly and not becoming overly damaged.

If you notice any signs of excessive damage or discomfort, rinse the bleach out immediately!

Rinsing and Conditioning 

Once the desired level of lightness is achieved or the recommended processing time has elapsed, it’s time to rinse out the bleach.

Use lukewarm water to gently wash out the bleach until the water runs clear.

Follow up with a moisturizing conditioner to restore hydration to your hair. 

Caring for Your Newly Bleached Hair 

After rinsing and conditioning, it’s essential to take care of your newly bleached hair.

Avoid excessive heat styling, use products specifically designed for color-treated hair, and deep condition regularly to maintain its health and vibrancy.


  • Strand Test: Always do a strand test and a patch test before you apply the bleach and developer mixture all over your hair. This helps to ensure you like the final color and also checks for any possible adverse reactions.
  • Protect your skin: Apply a thin layer of petroleum jelly around your hairline and on your ears to prevent the bleach from staining or burning your skin.
  • Don’t rush: Take your time when applying the bleach and developer mixture. Rushing through the process can lead to uneven results.
  • Watch the clock: Developer works over time, so don’t leave it on too long! Over-processing can lead to damage. Always follow the recommended time on the product instructions.
  • Use a good conditioner: Bleaching can dry out your hair. So, don’t skip the conditioner after rinsing out the bleach and developer. A good conditioner will help restore some moisture and shine.
  • Get help: If possible, ask a friend to help you apply the bleach and developer mixture, especially at the back of your head where it’s hard for you to reach. It’s always nice to have an extra pair of hands!
  • Stay safe: Always wear gloves and old clothes when dealing with bleach and developer. These substances can irritate your skin and ruin your clothes.

Frequently Asked Questions

What happens if you use 20 developer with bleach?

If you’re looking to lighten your hair by a level or two, using 20 developer with bleach might just be the answer you’re looking for.

But it’s important to keep in mind that everyone’s hair is different, and while 20 developer may be suitable for some, it might not be strong enough for others.

Darker hair types, in particular, may need a stronger developer to avoid turning orange!

Can I use any developer with bleach powder?

Yes, you can use any developer that matches the level of lift you’re looking for with your bleach powder.

For example, if you’re going for a subtle highlight, a 20-volume developer will be perfect.

On the other hand, if you want a more dramatic change, 30-volume or 40-volume developer might be required.

It’s important to always follow the instructions on both the developer and bleach powder packaging to ensure you get the desired result while minimizing any damage to your hair.

Will Level 30 developer lighten hair?

Absolutely, Level 30 developer will lighten your hair!

Level 30 developer is commonly used to lighten hair that is naturally dark.

It’s a step up from Level 20, offering more lifting power to achieve lighter shades.

But, remember this: a higher level of developer means more damage to your hair.

So, while it’s a fantastic tool for achieving those lighter hues, you should also be prepared to give your hair some extra love and care to keep it healthy. 

What do you mix developer with to bleach hair?

Developer is mixed with the bleach powder to create a concoction that lightens your hair

  • Developer: This is a hydrogen peroxide-based solution that helps open up the hair cuticle to allow the bleach to penetrate and do its magic.
  • Bleach Powder: This is the stuff that removes the pigment from your hair, effectively lightening it.

Note: Always remember to follow the instructions on the specific products you’re using. The general rule of thumb, however, is to mix one part bleach powder to two parts developer.

Does developer damage your hair?

The good news is that developer doesn’t necessarily damage your hair. In fact, it’s the bleach or color that could potentially cause harm.

Of course, over-processing your hair or using developer that’s too strong can cause some damage. 

But if you’re working with a professional stylist and using the correct level of developer for your hair type and color needs, you should be good to go!

Remember, healthy hair is always in style, so prioritize its care.

Parting Words

And there you have it! Everything you need to know about hair bleach and developer. It’s quite a lot to take in, isn’t it? But remember, practice makes perfect. 

Remember to always: 

  • Test your hair: Always do a strand test first. It’s the best way to avoid disappointment and damage.
  • Choose the right developer: Take into account your hair’s current condition and desired color. You can always ask for professional advice if you’re unsure.
  • Apply with care: Bleaching your hair can cause damage if you’re not careful. Always follow the instructions and never leave the bleach on longer than recommended.

But it all boils down to one thing: know your hair.

Everybody’s hair is unique, and what works for one may not work for the other. So get to know your hair, treat it with respect, and it’ll reward you with a stunning, vibrant color. 

So why not give it a try? With the right tools and knowledge, you’re all set to create your own unique style right from the comfort of your own home. You’ve got this! 

Remember: Your hair, your rules. Experiment, learn, and most importantly, have fun!

This article was written and reviewed by:

  • Nicola Freeman, Creative Director & Content Lead
    Creative Director & Content Lead

    With over two decades of passionate hair dyeing experience, I've experimented with nearly every shade imaginable. My journey began long before blogging; as an award-winning copywriter in London and New York, I shaped narratives for iconic brands. However, when friends sought advice during lockdown for at-home hair dyeing, I realized my true calling. Beyond being your hair color expert, I'm a mom of two girls, wife to artist Tony, and an avid soccer player!

  • Enza Piazza, Hair Stylist & Color Consultant
    Hair Stylist & Color Consultant

    I’m Enza Piazza, your go-to hair stylist and color consultant with over 23 years of professional salon experience bringing vibrancy and life to hair of all hues. My Italian roots from sunny Sicily infuse passion into every snip and color, a passion that’s been recognized with top honor awards including bridal and party hair at the National Hairdressers Federation’s Championships. After training in Surrey, UK’s most prestigious salons including Head Master Academy, I embraced the entrepreneurial spirit and set up Enza Hair Styling, offering tailored hair care for 13 years, and treating each client like family. Away from the salon, I cherish moments as a proud Nonna to grandson Joseph and as a playful companion to my Jack Russell, Bo.