How Long to Leave Bleach

How Long to Leave Bleach on Your Hair? A Brief Walkthrough for All Hair Types

Timing is everything. Similarly, bleaching is all about timing. While the outcome of it tends to benefit the hair of average individuals, making sure the process doesn’t exceed a certain amount of time is crucial. Failing to do so might result in short term, or even worse, long term consequences.

In this article, we will be covering and providing you with useful tips and tricks on bleaching and hacks you could follow to nail the timing perfectly. We will be dividing the volume developers into separate categories so that it’s easier for the readers to follow through.

We will also mention the harmful side of an unsuccessful bleaching attempt and  include the multiple ways in which it could be reversed.

How Many Minutes Should You Leave Bleach on Your Hair?

Bleach Hair

Bleaching allows a person to install a vibrant colored shade of dye on their hair. The chemical itself, however, is very harmful. It often tends to break up the cuticles to settle in, which is as harmful as it sounds.

Contrary to popular belief, leaving bleach on for too long doesn’t have a favorable impact on the visuals of hair, nor does it have a positive impact on one’s scalp.

Furthermore, a person’s hair type is directly related to the duration of bleaching.

For instance, if the wearer has hair that is naturally blonde, perhaps the bleaching process will only be good for 15 minutes. However, if the texture of the hair is on the thicker end, it might take around 20 minutes.

On the other hand, those with coarse hair will really struggle to keep up with the bleaching process. Not only will it be 40 minutes long, but it might also consist of two sessions as opposed to one. This is solely because of the texture and the sensitivity of it. Once it settles in, however, the final color will stick around for quite some time before requiring a redo.

Additionally, those with fine hair almost always have a time-friendly and advantageous experience when bleaching. Due to the soft cuticles their hair contain, it is easier for the bleach to blend in and adjust to the scalp.

Lastly, those with dark hair might have to clear up their schedule if they want to bleach their hair properly. Due to the texture, it might take up to 4 or 5 30 minute sessions for the wearer to see a noticeable difference in their hair if they were to apply bleach to it.

All in all, regardless of the hair type, bleach shouldn’t sit on the scalp nor the follicles for too long. The maximum time limit shouldn’t cross 45 minutes. Failing to do so might bring to the table an unfortunate circumstance with various disadvantages. A wearer should also use a volume developer that is catered to their hair type and color to attain the best results.

Pro-tip to Remember: The higher the volume, the higher the duration! 

An Intro to Volume Developers and Their Contribution to Bleaching

Before we discuss the types of volume developers that are catered to different demographics, perhaps it’d be a good idea to start off with an intro to volume developers.

Volume developers play a crucial role in the process of bleaching. They are oxidizing agents that are applied onto the hair to make the cuticles vulnerable enough to let new color in. Without their contribution, the art of coloring hair would be nothing but a myth.

Apart from allowing the cuticle to let in a new shade of color, volume developers also ensure the longevity of a dye. They also  increase the brightness of the hair and ensure the chances of having thick layers of colored hair.

How Long Should You Leave 10, 20, 30, and 40 Vol Bleach in Your Hair?

Volume DevelopersThere are 4 types of volume developers: 10, 20, 30 and 40. Each developer serves a different purpose, and caters to meet a unique set of requirements.

Additionally, while 10 volume developers do exist, they are more catered to those that are seeking darker hair, which makes them invalid for this writeup.

Regardless, here is a brief analysis on the types of volume developers and how they aid the bleaching process.

10 Volume Developer

A volume 10 developer offers a subtle amount of lift, but can be the best sidekick when your natural hair color is eerily similar to the new shade of dye.

For instance, if you already have blonde hair and want to lighten the shade by an insignificant amount, using a volume 10 developer will most definitely be the correct choice.

A 10 volume developer should be mixed with a demi color and shouldn’t stay on the scalp for longer than 30 minutes.

20 Volume Developer

A 20 volume developer offers a little more density to the wearers hair,  but is immensely effective at covering every faulty strand. It will not only help with bringing the lightest shade in your blond hair, but will also cover the gray hair strands effortlessly.

This is also a durable item and can safely stay on one’s hair for upto 30 minutes.

30 Volume Developer

A 30 volume developer is great for those that are seeking a shade that’s significantly lighter and long-lasting as opposed to the color of their natural hair. It enhances the hair and lightens it by upto 3 shades, and installs more dye onto the shaft.

In addition to the previous benefit, it also makes the hair look healthier and thicker, which can work wonders at social gatherings. However, in terms of duration, it is not as favorable as the previous two and should not remain on the scalp or hair shaft after 15 to 30 minutes.

40 Volume Developer

A 40 volume developer is meant for those that have a knack for hair with lighter and brighter shades. It is extremely efficient and can lighten the color of one’s hair by up to 8 levels.

For example, if your hair is naturally blonde, through the assistance of a 40 volume developer, you can change up your hair and give it a superior shade of platinum blonde.

Moreover, due to its high efficiency, a 40 vol developer should be washed off after 15 minutes. Failing to do so might make the scalp red, flaky, and full of scaly patches.

The Dark Side of Leaving Bleach on For Too Long

Dark Side of Leaving Bleach

Hair that is bleached looks stunning, especially due to the newfound volume that it gets from the overall process. Hair also tends to look more lively and vibrant, which increases its appeal even further.

While people believe that leaving bleach in hair for a longer period of time results in a more efficient outcome, that statement has yet to be verified and confirmed.

Although the end results are mostly favorable, one little mishap might make one’s bleaching journey unsuccessful. Similarly, leaving bleach on hair for too long might result in various consequences that will either be temporary, or stick around until eternity.

Bleaching products contain a series of harsh chemicals, and despite the benefits they bring to one’s hair’s appearance, the purpose of the item takes a u-turn and goes south when certain rules are broken.

Leaving bleach on one’s scalp for a long period of time might burn the scalp and bring in major issues like irritation, itching, and redness. In some severe cases, it might even cause the wearer’s hair to fall out in clumps.

This scenario is not just harmful for the body, but for the mind as well. Hair loss is not something that is easy to cope with, and tends to leave a huge dent in one’s self esteem. However, this situation can be avoided in multiple ways.

Visit a Trichologist

Trichologists specialize in the study of hair and scalp. They tackle multiple scalp related issues and should definitely be consulted before one considers bleaching their hair. Trichologists will assist you with figuring out the volume developer that will suit the wearer the best.

Go to a Stylist

This is probably the most important factor to take into account. Do not attempt to experiment with hair without having an adequate amount of knowledge on the specific activity. While going to a salon will take a chunk out of your pocket, your hair will receive the right care from the hairdresser throughout the process of bleaching.

Stylists also have awareness on the right amount, and can also avoid making contact with the scalp when applying bleach, which will save the visitor from various drawbacks.

Run a Patch Test

Carrying out a patch test beforehand is compulsory for most people. It will help the person with figuring out how their skin will cope with the applied product. It’s a very effective method of avoiding unfortunate events and is extremely time friendly as well.

Stay Alert

When gone wrong, the burning sensation from a failed bleaching attempt is very apparent. Make sure to be attentive and keep an eye out for a tingling sensation. Inform your stylist as soon as you feel it so that they can rinse the chemical off your scalp almost immediately and prevent further damage.

The Road to Recovery

While visiting a stylist is the better method, some people prefer carrying out the traditional DIY method of bleaching hair, which is often met with a negative outcome. This portion of the article is for those that have gone ahead with the procedure anyway and are now facing the music of their actions.

Below are some steps that should definitely be followed to kick start the recovery process of bleach damage.

Leave the bleach alone

Adding bleach to damaged hair will definitely make matters worse. Ditch the container and give your hair a break instead. Allow the scalp to produce some sebum and fight back against the dryness caused by the bleach. Layering harmful chemicals will only increase the chances of having hair that is permanently damaged.

Beat the heat

Damaged hair is extremely sensitive to heat. To take control of the situation, ditch the heat-oriented styling tools when fixing your hair. You may also wear a hat to protect your hair from the unbearably hot sun until it shows signs of recovery.

Trim off dead ends

Although bleach will damage every segment of the hair shaft equally, the ends will always be the most noticeable portions. To deal with that, visit your hairdresser and chop them off. Not only will your hair look healthier, but it will also allow your scalp to recover from the damage and make space for healthier hair to grow in the future.

Incorporate a Toning Conditioner

Apart from hydrating the hair, a toning conditioner corrects the color of one’s hair. It is very effective when used on bleached hair as it tones down the brassiness of it while providing an ample amount of moisture to the shafts.

Bonus Tip: Remember to be gentle with your hair and allow it some time to readjust and bounce back. It gets worse before it gets better. Make sure to treat your hair right during the darkest hours so that it’s calm after the storm.


Bleaching hair is often unpredictable and comes with a list of pros and cons. It might also be very inconvenient for a novice to understand the complexity that it holds, which explains this portion of the write-up. To make the learning process a piece of cake, we have addressed a series of questions regarding the duration of bleaching and placed them below.

1. How long should I leave bleach on my hair?
Regardless of your hair type, bleach shouldn’t sit on your hair for more than 45 minutes. Failing to do so might make things go south as it will not only start hurting your follicles, but also burn your scalp. As much as we’d love to support the thought of bleaching hair at home, we believe that the best outcome is only achieved through the helping hand of a professional.

2. What will happen if I leave bleach on my hair for too long?

Crossing the initial duration of bleaching hair might damage the ends of your hair and irritate your scalp. The scalp might also become flaky, which might cause the wearer to lose a heavy amount of hair.

However, the outcome can definitely be reversed with the help of a  proper and gentle hair care routine.

3. Should I shampoo my hair right after bleaching it?

Bleaching often dries the hair out by absorbing all the natural oils that the scalp contains. For that very reason, shampooing the hair right after wouldn’t be the wisest idea as it contains Sodium Laureth Sulfate (SLS). SLS is a chemical that is used to control the production of sebum, and using it on bleached hair might dry the scalp out even further and make it flaky.

For best results, make sure to gently rinse the scalp after bleaching the hair. You may shampoo the hair to get rid of the residue 48 hours after getting the new dye, so that the buildup fades away without hampering the new shade of the dye. 

Final Verdict

When all is said and done, our main incentive is to provide our readers with an adequate amount of information on the specific topic we cover.

Identically, we hope this article allows you to have a better approach to bleaching and supplies you with useful advice on its timing. We also hope the latter portions boost your confidence and allow you to control the outcome if the process of bleaching goes wrong.

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