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 this blue-black hair, you aren’t limited in the ways you can wear it. Different coloring techniques can help make the look totally your own. Here are a few ideas to inspire your transformation.

Dark blue-black

For a subtle take on fantasy color, opt for dark blue-black hair. The inky, midnight-blue hue is unique and surprisingly sophisticated, especially when paired with sleek, glossy strands.

Blue-black balayage

If you’re not ready to commit to an all-over blue-black hair color, 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’re an at-home hair color novice, you may want to hit 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.

Black with blue money pieces

Another fun way to experiment with black and blue hair: money pieces. Essentially, this trend involves coloring just the strands around your face. It’s 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.

Iced navy

Navy blue is often associated with official uniforms and preppy ‘fits, but as a hair color, it’s anything but boring. Opt for a dark navy with silvery undertones for a metallic effect that beautifully complements cool skin.

How To Care for Blue-Black Hair

Any time you color your mane with permanent hair dye, switching up your haircare routine is a necessity. Without tweaking your routine, you’re likely looking at fast fade-out and dull lengths. To keep you ahead of the game, be sure to follow the steps below to help keep your blue-black hair looking and feeling its best.

Switch to a color-safe shampoo and conditioner

After dyeing your hair, it’s a good idea to swap out your regular shampoo and conditioner for a system designed for color-treated hair. Coloring your hair can be damaging—even if you opted to entrust your transformation to a pro—so we recommend opting for a reparative system, such as the L’Oréal Paris EverPure Sulfate-Free Bond Repair Shampoo and L’Oréal Paris EverPure Sulfate-Free Bond Repair Conditioner. The duo helps repair damaged, color-treated hair from the inside out and leaves the hair feeling stronger and smoother with continued use. If you’re facing lots of damage, you may want to consider pre-treating your mane with the L’Oréal Paris EverPure Bond Strengthening Pre-Shampoo Treatment before lathering up. Make sure to shower in lukewarm water, too, as hot water can strip your strands of much-needed moisture.

Deep condition your hair weekly

It’s always smart to show your color-treated strands some extra love. Once weekly or as needed, swap out your conditioner for a deep conditioning hair mask, such as the L’Oréal Paris Elvive Total Repair 5 Power Restore Multi-Use Treatment. The protein-packed formula melts into the hair fiber and helps repair the strands for silkier, healthier-looking hair. If deep conditioners aren’t your thing, you can also use this versatile formula as a leave-in treatment or a fortifying co-wash.

Limit heat styling

The high temperatures of hot tools can do a number on your mane. If your hair is already weak from color processing, it’s extra important to be gentle with your strands to avoid damage. When possible, skip the hot tools and opt for a heatless hairstyle to give your tresses a break. If you must use hot tools, set them to a lower heat setting and prep your strands with a heat protectant to help shield against damage. For the latter, we love the L’Oréal Paris EverPure Bond Repair Hair Oil-in-Serum, which boosts shine, strengthens the hair, and protects against temperatures up to 450 degrees Fahrenheit.

Commit to regular touch-ups

Even with permanent hair color, you’re looking at root growth every eight weeks or so. Once you start to notice a sliver of roots, pencil in time for a touch-up when you can. Until you’re ready to hit the salon (or color your roots yourself), conceal regrowth with a temporary root touch-up spray, such as the L’Oréal Paris Magic Root Touch-Up Spray in Black.

Next Up: How To Dye Hair at Home in 8 Easy Steps

Photo courtesy of L’Oréal Paris