Can You Mix Hair Dye And Developer? Expert Answer + Calculator

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So you want to dye your hair at home? You’re not alone!

A lot of people like to take on the challenge of dyeing their own hair. It can be a fun way to change up your look, and it’s definitely cheaper than going to a salon.

But before you start mixing up developer and hair dye, there are a few things you need to know. Like, what kind of formula should you use? And how do you know if your hair is light enough for the color you want? How much developer do you really need?

We’ve got all the answers for you right here.

Can you mix hair dye and developer?

Yes you can! Mixing these products together means you can change the color of your hair easily at home.

Developer contains hydrogen peroxide and can be used to lighten hair, remove unwanted tones and create different colors.

Developer works by activating the hair dye formula and helps open the hair cuticle so the color molecules can penetrate the hair shaft. Without a developer, most permanent hair dyes won’t work effectively.

The concentration of hydrogen peroxide in the developer determines its strength, typically labeled by volume numbers like 10, 20, 30, and 40. The higher the volume, the more lift (or lightening) the developer provides.

The ratio of hair dye to developer you need – the amount of each – can vary based on the brand, type of hair dye, and desired result. Always follow the manufacturer’s instructions when mixing!

Common ratios include 1:1, 1:1.5, or 1:2, but it’s best to always read the specific product directions for the best results.

Ratio of Hair Dye to Developer Calculator!

Need help working out your Hair Dye/Developer amounts by ratio and exactly how much you need? Just use our Hair dye to developer ratio calculator!

Hair Dye Developer Ratio Calculator

Ratio Volume(oz)

What happens if you mix developer with hair dye?

Adding more developer to hair dye will lighten your hair color, while adding less developer will darken it.

If too much is used, it’ll dilute the colorant so your hair color won’t be as strong.

Use too little and the hair dye might be too dark, to might not even color your hair at all.

Be sure to read the instructions on each box and only mix what is recommended!

Mixing them together can cause a number of different things to happen:

  • Your hair could become too light or too dark.
  • It could become damaged or frizzy.
  • You may not get the desired results.
  • The color may not last as long.

So, be careful and make sure to read the instructions on each box before mixing anything together!

What developer do I need?

For shade darker or same shade or 1 shade lift, use 20 vol.

For 2~3 shades lighter, use 30 vol.

For 4 shades lift, you will need 40 vol.

*This is a rough guide. It all depends on things like your base color, whether your hair is bleached etc!

Can I put developer in hair dye?

The quick answer is yes, you can put it in hair dye.

But you need to determine the right mix for your desired result as it can make a big difference for your color.

If you use too little developer, you won’t be able to open the hair cuticle enough so the dye won’t penetrate and stick to your hair.

Using less developer than suggested reduces developer activity, resulting in insufficient color pigment deposits in the hair.

There may not be enough strength to get the desired lift for lighter colors, which means the color will be darker than you planned!

Use too much and you’ll be lightening the hair but not depositing enough hair dye, resulting in a false color that fades quickly.

The processed color may be less dense and opaque than usual, ammonia levels will be diluted, and the color can’t penetrate the cuticle well enough to cover gray hair.

can you mix hair dye and developer hairdresser tools

Can I mix developer with box dye?

Again, the answer is yes!

But you don’t really need to.

Many at-home hair dyes come with it included and pre-mixed in the right amounts, so you don’t have to add any more.

Different dyes have different volumes and concentrations, so following the instructions is key to making sure you don’t damage your hair.

Can I mix developer with hair dye to make it lighter?

No – this is not a recommended practice and here’s why.

When you mix it with hair dye, you are increasing the volume of ammonia in the mixture.

And when there is too much ammonia in hair dye, it can cause your hair to break and fall out.

So, if you’re looking to lighten your hair, it’s best to stick with a bleach that is designed for lightening hair.

Can you mix two brands of hair dye?

Again, it depends on the brands and what is in them!

But in general, you can mix two different brands of hair dye as long as they have the same volume measurements (ie., teaspoons, tablespoons, ounces).

Just be sure to follow the instructions on both boxes for mixing them together.

Experimentation may be necessary to find the right proportions for your hair type and desired color result.

But once you do, you can create custom colors that aren’t found on any box. So get creative!

How to mix hair color.

We have a great guide on how to mix hair color to create bespoke shades that suit you skin tones, eye color and natural coloring in Hair colour mixing chart. The easy guide to mixing colours!

You can also watch this easy how-to video to find out how to do it!

Can you mix developer with permanent hair dye?

Yes, you can mix it with permanent hair dye.

But using a different developer than what is recommended on the box can change the results of the color.

If you’re looking to lighten your hair, it’s best to stick with a kit that is designed for lightening hair.

Can you mix developer with semi-permanent hair dye?

Semi-permanent hair dyes generally don’t contain developer, so there is no need to mix them together.

But you may have to bleach your hair first for the color to show up.

You should only mix developer with DEMI-permanent hair colour, not semi-permanent.

If you need to dilute the dye, just use a clear conditioner.

Can you mix conditioner with hair dye and developer?

The answer is yes – you can mix these products together!

However, it’s important to keep in mind that doing so may dilute the formula and reduce the life of your hair color.

Hair dye needs a certain chemical balance to make the color result effective. That’s why everything you need comes ready to go in the box.

If you’re looking to add extra conditioning to your hair dyeing process, we recommend using a deep conditioning treatment before you dye your hair.

This will help keep your hair looking healthy and vibrant for longer.


You can also mix hair dye with shampoo to refresh your color if it’s not quite needing another color top up just yet!

Can you mix hair dye with bleach powder and developer?

Bleach powder and developer need to be mixed in a specific ratio in order to achieve the correct lightening effect.

Adding hair dye to this mixture will not have the desired result, so it is best to avoid doing this.

If you’re looking to lighten your hair color, we recommend using a products that are specifically designed for this purpose.

A bleach wash is a gentler way of lightening your hair if you only need to lift it a level or two.

This will give you the best results.

Parting words.

So there you have it!

You can mix hair dye with developer and conditioner, but it’s important to keep in mind that doing so may dilute the formula and reduce the life of your hair color.

As always, talk to your hair dresser for some expert advice if you’re not sure.

They’ll help you determine the perfect solution for you!

This article was written 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!