How Much Hair Dye Do I Need?

Are you worried about how much amount of hair dye you will need to color your hair completely?

Nowadays, coloring your hair with warm colors is a new trend to look stunning and to feel good. Your hair color can range from red, purple, or blue depending upon what you want to express and there is no limitation in expressing yourself. People are confused about the exact amount of hair dye they need to color their hair. Well, here are some guidelines to end this confusion. This guideline is based on the thickness and length of your hair.

The answer is it depends on the brand and how dark you want your hair to be. Generally, most people use 1-2 ounces of dye, but it’s always best to read the instructions on the bottle.

If you have light hair, you will likely only need 1 ounce of dye. If you have dark hair, you may need up to 2 ounces. Be sure to mix the dye thoroughly before applying it to your hair, and always do a strand test to make sure the color is what you want.

Imagine you have to attend a meeting in the morning and you are dyeing your hair at night and suddenly you ran out of the hair color after dyeing half of your hair!!! So what to do if not enough hair dye?

To avoid such kind of situation, you have to follow certain guidelines before dyeing your hair.

Firstly, the main apparatus you are going to need for coloring your hair is a box of hair dye, a mixing bowl, and a brush.

Before applying the hair color, consider the following basic preparation:

  1. Wash your hair one or two days before applying the hair color.
  2. Protect your hair and home from hair color stains. Wear an old t-shirt during the application of hair color.
  • Wear gloves when you apply the hair color.
  1. Properly brush your hair.
  2. Pay attention to all the caution and warnings written on the box of a hair color kit.
  3. Don’t skip the patch test.

Next, you have to follow the instruction which is written on the box of your hair dye about getting the ratio of the developer to the cream in the right amount. All hair dyes work best on dry and unwashed hairs. Try using ammonia and peroxide–free hair dye to avoid damage to your hair.

Based on Hair Length

Based on Hair Length

For Short Hair:

If your hair is short, then you will need only about 2 to 3oz of hair dye, if you have a plan to cover your hair completely.

Sometimes the dye is left over and it starts getting darker in color, so it is suggested not to use the leftover dye, be it permanent or semi-permanent hair color. In this case, try to use the single color kit to avoid wastage. There are different brands that offer 2 to 3oz of dye in their color kit.

For Medium Hair:

Shoulder-length hair is considered medium-length hair. As compared to short hair, this hair length is difficult to dye when it comes to applying the right amount of hair color.

For medium hair length, 3 to 4oz of hair color is enough for full coverage. You can buy two boxes of hair color kits to completely cover your hair. You can use 50 / 50 developer/dye ratio to get better results.

For Long Hair:

If you have long hair, then it would be difficult to determine the exact amount of hair dye you will need.

Long hair can range from a few inches below the shoulder to all the way to the waist.

In both cases, it is better to buy three 2oz boxes of hair color kits because it would be better to have more hair dye rather than having less amount. If the dye finishes before complete coverage of hair, then you will have uneven color shades.

For estimating the exact amount of hair dye, here are some guidelines.

  • If the hair is 2 – 4 inches below your shoulder, then you will need about 4oz of hair dye for the full coverage of hair.
  • If the length ranges from 5 – 8 inches below your shoulder, then you will need 8oz of the hair dye.

Based on Hair Thickness:

Based on Hair Thickness:

Many people do not consider the thickness of the hair as an important factor, before dyeing their hair. But as far as the amount of dye is concerned, it is an important factor because it has an effect on the absorbance of hair dye.

Depending upon the thickness of hair, there are three sections of hair thickness (fine, medium, and thick hair) that must be kept in mind before applying the hair color. If you want to determine that to which category your hair belongs, you can try the following trick.

  • Take a rubber band and try wrapping it around your hair as many times as you can into a ponytail.
  • If you can wrap it around four times, then your hair belongs to the first category i.e fine thickness.
  • If you can wrap it around three times, then you have medium thickness.
  • If you can wrap it around two times, then you have thick hair.

For Fine Hair:

For Fine Hair:

This is the easiest section of hair thickness when it comes to coloring your hair. But there is one disadvantage of this type as it is more prone to damage as compared to medium and thick hair. So keeping this in mind, the recommended amount of hair color is around 2 to 3oz, if you have short hair.

For Medium-Thick Hair:

This is the most accepted section of thickness and a normal hair type. All the hair color kits are designed by keeping this category in mind. If you have this type of hair, then you can freely apply any amount of hair color, keeping the length of your hair in consideration.

For Thick Hair:        

For Thick Hair

This category is the most resistant hair type when it comes to applying hair color because of its volume and it is also difficult to control. This means you will need more dye to cover your hair completely.

If you have short thick hair then it is better to use the upper limit of the recommended amount which is 2.5 to 3oz. Also, purchase extra hair dye just in case you run out of the dye before complete coverage.

As mentioned above one should try not to use ammonia and peroxide-containing dyes. Hydrogen peroxide is added into some dyes which are very harmful to the hair and skin. According to Journal of Dermatological Science, many people visit dermatologists complaining about excessive hair loss after applying a certain dye.

The studies suggest that this excessive hair loss is due to its cytotoxic (toxic to living cells) effect. Peroxide can also cause inflammation of the skin which is termed ‘dermatitis’. Peroxide can also cause scalp burns.

  • After dyeing your hair, you should wait for 72 hours before shampooing because it will lighten your hair color faster.
  • Try to use sulfate-free shampoo and conditioner.
  • Add dye to your conditioner. It will slightly re-dye your hair.
  • Turn down your water temperature because after dyeing, your hair cuticle is opened and hot water can wash out the dye from your hair.
  • Try using slightly warm water and then rinsing it with cold water after conditioning.
  • If you want the hair color to last longer then you should try not to wash your hair daily because every time you wash your hair, you will also wash away a little bit of hair dye every time.
  • Try washing your hair 2-3 times a week in order to retain your hair color for a longer period of time. When you wash your hair, try to dry them naturally and avoid using a hairdryer as the as from it can damage your hair color.
  • On your off days of not washing your hair, try using color-safe dry shampoo which will refresh your hair and give the effect of a blowout.
  • Avoid using chlorine or saltwater because chlorine has a bleaching effect and it will lighten your hair color. Avoid using hair sprays or any product containing too many chemicals.
  • Avoid UV rays after coloring your hair because it will have damaging effects. When you go outside in the Sun, try to cover your hair with a hat or scarf.
  • Get your hair trimmed every two if you have damaged hair.
  • Try to keep your hair hydrated as much as possible because your hair becomes more brittle and prone to breaking off after applying the hair color.
  • Try using hair masks in place of a hair conditioner. Hair masks can make your scalp hydrated. Avoid using thick hair masks.

Frequently Asked Question & Answers (FAQs)

Question 01: How much hair dye should I order?

Answer: If you have long thick hair then you will need 3 boxes of hair color kits for an ideal result and the recommended amount is between 2oz to 8oz. if you have short thick hair then the recommended amount is between 2.5 to 3oz. It all depends on the length and thickness of your hair.

Question 02: What can happen if you run out of dye halfway through dyeing your hair?

Answer: If you carefully do not calculate the exact amount of hair color you will need according to your hair type, then you will end up in this kind of situation because as a result, you will have two different shades which will not look good.

To avoid this kind of situation, you should have the exact amount of dye you will for the full coverage of your hair.

Question 03: Is 4 oz. of hair dye enough for a full head?

Answer: It all depends on the thickness and length of your hair. If you have thick short hair then 4oz would be enough. But if you have long thick hair then 4oz would not be enough as long thick hair needs extra dye. For medium-thick hair, it would be enough for the full coverage.

Question 04: How much hair dye do I need for roots?

Answer: If you have short hair then one box of hair coloring kits would be enough. If you have long hair, then you will need 2 boxes of hair coloring kits. Generally, 2 boxes are enough if you want to do root touch-ups. It is recommended to do a root touch-up every 6 – 8 weeks because your root grows faster than the rest of the hair because of the heat of your head.

Question 05: Should I use the whole bottle of hair dye?

Answer: It is recommended not to waste the dye. To calculate the amount of dye you will need according to your hair type before mixing the developer and dye.  Try to get the developer and dye ratio according to your hair length and thickness.

Question 06: What happens if you put too much developer in hair dye?

Answer: If you put too much developer in hair dye, your hair color will be more and runny and it will not give the desired color which may end up lightning the hair and not depositing enough and the resulting color will not be long lasting.  You should always mix the right amount of developers in order to get the desired results.


The amount of dye you need to color your hair totally depends upon the length and thickness of your hair. You, simply, need to find out your type of hair and apply the recommended amount of hair color according to your hair type. Many people do not go through the ingredients of any hair dye before applying it. Try to use peroxide and ammonia-free hair color kit in order to avoid your hair being damaged because ammonia damages the skin and hair.

Ammonia when mixed with water forms ammonium hydroxide which causes skin irritation and skin burns. Try not to waste the dye and this can be achieved by using the recommended amount of hair dye. You can try different methods to determine your hair thickness. Before applying the dye, try to take all precautionary measures to have the long-lasting effects of the dye you are using.

Allice Smith

Allice Smith is a hair care lover when she was a teenager. Her major was a beauty when she was in college. She is a makeup artist. Now she is also a writer for our website. She writes a lot of haircare posts with very actionable tips.

Related Articles

Leave a Reply

Your email address will not be published. Required fields are marked *

Back to top button