* Your hair will become black. This is the most obvious outcome. The black dye will deposit color onto your existing brown hair.
* It will likely cover the brown completely. Black dye is very strong and pigmented, so it should effectively cover most shades of brown. However, the exact result can depend on the specific dye used and the porosity of your hair.
* It will be a significant change in appearance. Going from brown to black is a drastic change. It will affect your overall look, potentially making your complexion appear lighter or highlighting certain facial features.
* It will be difficult to go back to brown (or lighter) later. Black dye is notoriously difficult to remove. If you decide you want to go back to brown or blonde in the future, it will likely require multiple salon visits, color stripping, and potential damage to your hair.
* You may need to adjust your makeup. Black hair can make you look washed out if you don't adjust your makeup to complement the new color. You might need to use brighter blush, lipstick, and eyeshadow.
* You'll need to touch up the roots frequently. As your hair grows, the brown roots will become visible, creating a noticeable contrast with the black dyed hair. You will need to touch up the roots regularly to maintain a uniform color.
* Consider your skin tone: Black hair can look stunning on many people, but it's important to consider your skin tone. Generally, it suits people with cool or neutral undertones. If you have very warm undertones, black hair might make your complexion look sallow.
Before you dye your hair black, consider these factors:
* Is it a good choice for your skin tone?
* Are you prepared for the high maintenance of root touch-ups?
* Are you sure you want to commit to black hair for a long time, considering the difficulty of removing it?
* Would you consider using a semi-permanent or demi-permanent black dye first to test the look and see if you like it before committing to a permanent dye? This can fade more easily than permanent dye.
It's always a good idea to consult with a professional hairstylist before making a drastic color change. They can assess your hair and give you personalized advice.