How Long to Leave Hair Dye In

how long to leave hair dye in

Coloring your hair can add luster and emphasize texture back, making your hair appear more interesting and vibrant. However, hair dying can sometimes end in disaster, especially if you’re coloring at home for the first time. 

Two common mistakes in hair coloring are leaving the hair dye too long or too short. The result? There is a possibility of an extra deposit of pigment in the hair if you leave the hair dye on for too long or that the color won’t have enough time to penetrate the hair if you leave it too short.

With all things to consider – the application of hair color, time of exposure, restoring care, shampooing, and an additional time if the roots need separate coloring – how long exactly will you leave hair dyed in for best results? 

Keep reading to find the answer. I’ll also share things you need to know before coloring your hair and common dyeing mistakes you should avoid.

How Long to Leave Dye in Hair for Best Results?

The timing of the procedure varies. It depends on whether the hair coloring is done at home or in the salon. The difference is sometimes significantly, sometimes slightly.

This is because the time depends on the stages of work, the technique, the desired result (some prefer complex coloring that requires foiling schemes),  as well as the skill of the hairdresser. Whether the hairdresser is in a rush or is distracted are other factors you should consider.

But generally, most hair dyes should sit in the hair for at least 30 minutes to 45 minutes. Anything longer than that is not advised. It needs just enough time (30 minutes) for the peroxide and ammonia to work their way to the hair strands and into the cuticle so that it will alter the hair’s natural pigment. 

The remaining 15 minutes are for the hair color to fully permeate and develop the hair. And don’t worry if you’re in doubt because the product packaging almost always tells you how long you should leave the hair dye in your hair.

What Happens If You Leave Hair Dye Too Long?

Leaving the hair dye longer than recommended may give your hair a more intense tone and darker color. On the other hand, it can also damage your hair.

Leaving permanent hair dye on longer is sometimes different in semi or temporary dye. Still, it is generally not a good idea because the smell of your hair causes headaches or your scalp will become inflamed. 

When dyeing fine hair, keep an eye on how the hair color is developing so you can rinse it off earlier. This type of hair is more susceptible to damage and is at risk of over-processing. On the other hand, dyeing medium hair (normal hair thickness) doesn’t need special treatment before coloring.

How Often Can You Dye Your Hair Safely?

Innovations in hair color technology mean that enhancing or altering your natural hair color need not be damaging, but how it is done, how often it’s done, and how you care for your hair between coloring matters.

Temporary Hair Dye 

Temporary hair color lasts a short time and often comes out after your first shampoo. If you prefer these dyes, they are not harmful or harsh to your hair, and you can repeat the process as often as you want.

Semi-Permanent Hair Dye

Semi-permanent dyes can last up to 3-6 washes and can be done every week. This is safe because the color does not penetrate the hair, nor does it lighten or “lift” your hair’s natural color.

Semi-permanent hair dyes don’t contain peroxide, unlike permanent and demi-permanent hair colors. So, although they can darken the hair, they cannot lighten it. These hair colors cannot take you from brown hair to blonde but can take you from a honey blonde to a brunette.

Permanent Hair Dye

Permanent dye has more potential for hair damage than temporary hair dye because of the chemistry involved. You can count at least 6-8 weeks before you repeat the hair coloring process to spare your hair from damage: the less frequent hair dyeing, the better.

Regardless of the condition of your hair before you color it, it is essential to give it a break between color treatments, especially if what you’re using is a permanent hair dye.

See Related Post: Best Permanent Red Hair Dye

What to Do Before Coloring Your Hair

Rule 1: Lay off the heat tools 

Leave your hair freshly shaped, and avoid using heat tools before coloring your hair. When the shape of your hair is altered, the shadow and light reflected will look different. So, if you want to maximize the look, a natural, fresh shape of the hair is the best way to go.

Rule 2: Don’t go more than two shades darker or lighter than your natural hair color

Hair colorists would agree that you should stay within two shades darker or lighter than your natural hair color. For instance, if your hair is dark and you want a lighter color, don’t go for more than two shades. This is particularly important for brunettes who’d love to go blond.

Also, choose a hair dye color with “neutral” or “natural.” These dyes are better suited for those with gray hair to achieve a more natural result. The “wig effect” (dyed hair does not appear natural) can occur if you constantly color your hair with ammonia.

See Related Post: What Color Neutralizes Pink Hair?

Rule 3: Do a patch test

Before coloring your hair, test a new hair color on a small area of your hair or skin before applying it to your entire head. If your skin looks drab or the color is too ashy, you risk a scalp reaction. There’s a possibility that your skin cannot tolerate the chemicals.

Rule 4: Dye only new growth, if needed

There’s no need to color your entire strands each time you notice color fading. Doing so will only cause discolored ends, unnecessary damage, bands of darkness and lightness, and color buildup. A good rule of thumb is to avoid color overkill.

Rule 5: Shampoo your hair 24-48 hours before the coloring session

Most hair dyes work better on hair that is not freshly shampooed or washed. Skipping a shampoo at least 24 to 48 hours before the coloring session allows oils to build up on the scalp, which helps protect it against irritation caused by the dye.

How to Make Your Hair Color Last Longer

If you want to maintain and preserve your hair color at home, follow these tips below:

  • Wash less, use dry shampoo more

Your hair is in a delicate stage after a new hair dye. This is why colorists would recommend a 48-hour waiting time before washing your hair. So, avoid shampooing right away because the color may fade quickly.

After three days, you can use dry shampoo to preserve the hair color longer. Dry hair shampoo smells great, keeps your hair fresh all day, and removes the odor. They absorb the oil but don’t leave your hair chalky. 

  • Use a deep conditioner.

Use a deep conditioner containing hydrating ingredients such as jojoba, argan, coconut oils, and linseed extract. All these hydrating ingredients help smooth the cuticle. 

Ideally, you should deep condition underneath a warm towel or shower cap to keep the moisture in. This will also open the hair cuticle, and when it’s time to rinse it with cool water, your locks will reap all the hydrating benefits.

  • Swim smarter

Use a hair protector with SPF when in the ocean, pool, or you have to expose yourself to the sunlight. These things can keep your hair color from fading.

  • Avoid hot showers

Hot water decreases the life of color and dries the skin. The warm temperature opens up your hair cuticle, releasing the color. Rinse your hair with room-temperature water and condition it as much as possible.

Hair Coloring Mistakes You Should Avoid

1. Your hair color came out uneven

So you leave the hair color for 30 to 45 minutes, but when you wash it out, the result is more like a balayage and not a single dye. It’s not something you wanted. Why is that? 

It could be due to the heat from your scalp, which affects the color results. It gave additional energy during the hair color processing that caused the color to be one shade lighter at the roots. To prevent this, apply the hair dye on your ends first before the roots.

If it’s a root touch-up, put the color to the new hair growth first to prevent over-pigmenting in the rest of your hair that has already been colored. 

See Related Post: How to Blend Dark Roots With Blonde Hair at Home

2. Applying dye to the scalp

Unless you need to do a root touch-up or cover your gray hair, keep a distance of about one inch from the scalp when dyeing your hair. Avoid coloring the scalp area as possible because the color contains a heavy dose of chemicals.

3. Dyeing your hair if it’s already damaged or dry

As tempting as it can be, avoid dyeing your hair if it is already damaged or dry. If your hair is particularly dull-looking, crunchy, and dry, give it some TLC and wait for at least 8 to 10 weeks before another hair color. Make sure to condition your hair every time.

4. Mixing the hair dye components in the wrong proportion

The developer and the colorant are two essential components in hair dyeing. Most hair dye packages come with instructions on using the product or mixing them. Combining these components in the correct proportion is essential to achieve the best hair color (ideally, two parts developer and 1 part color). 

5. Using random brush movements

Aside from leaving hair dye in the specified time, you should also systematically apply the color in sections to achieve the best results. 

If you have thick hair or the person you’re applying the color too has thick hair, it is best to use the stand-by dye strand for even color distribution. If you observe salons, they will section the hair in four sections – ear to ear and down the middle. 

Apply the hair color from the bottom (neck to the crown) and continue to the front hairline. Moreover, always begin with regrowths to mid-lengths.

The Bottom line

Fresh hair color can boost your confidence and mood and elevate your look. The opposite can happen in a lackluster dye job. And because you don’t want to leave your home or the salon filled with regret and horror, you should be mindful of not dyeing your hair too long.

Also, give your hair a break between color jobs and protect your tresses by using color-safe products after coloring your hair.

TL;DR: how long to leave hair dye in your hair? – 30 to 45 minutes.

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