How To Get an On-Trend Blue-Black Hair Color

Separately, blue and black hair colors are both undeniably cool and work well for anyone seeking an edgier look. Together, though, they make magic—or, to be more specific, they make blue-black hair. This unique inky hue is dimensional, dramatic, and full of shine, and unlike many cool-toned hair colors, it can complement a wide range of complexions. If you’ve been toying with the idea of trying the trendy look for yourself, there’s no time like the present. Ahead, we’ll introduce you to our favorite blue-black hair dyes, share tips on picking the right formula for you, and explain how to keep your midnight-toned mane looking its best between touch-ups.

What Is Blue-Black Hair?

Blue-black hair is a soft, cool-toned black shade with just the slightest hint of blue. In low lighting, it tends to look like a classic jet-black hue. However, in direct sunlight, the shade’s brilliant blue undertones show through, making the color appear midnight blue or even navy blue rather than black. As it’s cool-toned, a blue-black hair color is an excellent pick for those with cool-toned skin. However, because the blue tones are relatively subtle, this unexpected shade can work well for those with neutral and warm complexions, too.

Is Blue-Black Hair a Natural Color?

No, blue-black hair is not a natural hair color, though black hair is. According to the National Institutes of Health (NIH), black hair contains a high concentration of eumelanin, the pigment that gives hair its color. (For reference, lower amounts of melanin yield brown or blonde hair, while a different type of melanin—pheomelanin—is responsible for red hair). However, there isn’t any naturally occurring pigment that gives hair a blueish cast, which means black-blue hair can only be achieved via the use of a blue-black hair dye.

How To DIY a Lustrous Blue-Black Hair Color

An all-over blue-black hair color is fairly easy to achieve at home, so long as you have the right hair color kit on hand. Since this shade is so dark, you typically won’t need to bleach your hair before applying your dye, either (though it’s always a good idea to read the directions on the box for specific instructions).

If you’re new to at-home hair transformations, consider picking up the L’Oréal Paris Colorsonic Hair Color Device. The high-tech device instantly mixes your chosen hair dye formula, parts your hair, and evenly applies the dye from root to tip at the press of a button, taking all the guesswork out of dyeing your hair. To use it, you’ll also need to pick up a hair color cartridge—for blue-black hair, naturally, we recommend using the L’Oréal Paris Colorsonic Permanent Hair Color Cartridge in Soft Black Blue Black.

Tips for Choosing a Blue-Black Hair Color

Blue-black hair isn’t just one color—there are plenty of variations of the velvety hue. If you have warmer skin, you’ll likely do best with a subtler shade, as pure cool tones may make you look washed out. Try DIY-ing the look with the L’Oréal Paris Féria Multi-Faceted Shimmering Permanent Hair Color in Starry Night. The soft black shade has the slightest hint of navy undertones that you may not notice until you step into direct sunlight.

On the other hand, if you have cool skin (or simply want to go all-in with a fantasy color), opt for something more distinctly blue. We love the L’Oréal Paris Féria Midnight Bold Multi-Faceted Shimmering Permanent Hair Color in Cosmic Azure. Keep in mind that the darker your starting color, the deeper your results will be.

Finally, if you’re not ready to commit to an all-over color, you can also opt for highlights. We’re big fans of inky-black hair with deep blue balayage—the subtle highlights will add dimension without requiring you to touch up your roots every four to six weeks.

5 Blue-Black Hair Color Ideas We Love

When it comes to blue-black hair, there are no limits in the ways you can wear it. Different coloring techniques can help make the look totally your own.

Dark blue-black

For a subtle take on fantasy color, opt for an all-over dark blue hair dye. The inky, midnight-blue hue is unique and surprisingly sophisticated, especially when paired with sleek, glossy strands. You can achieve this at home using the L'Oréal Paris Superior Preference Fade-Defying Shine Permanent Hair Color in Blue Black for that signature reflective finish.

Blue-black balayage

If you’re not ready to commit to an all-over blue-black hair dye, balayage can be a great way to dip your toes in. You can do balayage at home, but it’ll require several rounds of processing to achieve black hair with inky blue highlights. If you are an at-home hair-color novice, you may want to head to the salon to achieve this look.

Violet black

Blue-black hair usually leans more navy than violet, but that doesn’t mean you can’t make the hue your own. Opt for a dark, cool purple dye instead of a blue-black hair dye for a fun departure on this colorful trend. The L’Oréal Paris Féria Multi-Faceted Shimmering Permanent Hair Color line offers several purple-toned shades that provide that same multi-dimensional shimmer. For example, try Cool Amethyst for an ashy purple look or Midnight Violet for a deeper shade.

Black with blue money pieces

Another fun way to experiment with black and blue hair is by adding money pieces. This trend involves coloring just the strands around your face to frame your features. It is a lot like face-framing highlights, only instead of brightening brown hair with blonde pieces, you’ll be punching up a jet-black mane with cool blue streaks. This requires precision application, so take your time when sectioning out the front pieces of your hair.

For this look, try L'Oréal Paris Féria Multi-Faceted Shimmering Permanent Hair Color in Jet Black for a deep, dramatic black base.