“Concave Layers” Are Going Viral On TikTok — Here’s Why

We thought we'd left the big, bouncy blow-dry in the '90s, but the look has made a comeback lately — and it's all thanks to TikTok. The trend started with none other than Cindy Crawford, and even now, the '90s supermodel is still a hair muse for many. Bolstered by daughter Kaia Gerber, it's clear to see why hair tutorials on how to get buoyant volume are everywhere again.

On TikTok, we've already seen the success of the '90s-inspired C-shape haircut (face-framing layers that cup the face and enhance thickness), not to mention the oval-layer haircut (polished layers styled to resemble voluminous O-shapes hugging the face). But if social media is anything to go by, there's a new haircut technique in town and it's set to lend all hair types a whole lot of volume.

Enter: concave layers.

Concave layers have 38.4 million mentions on TikTok, which is always first for hair-trend inspiration, from the wolf cut to liquid brunette color. While concave layering isn't strictly new, the method (and the easy volume it creates) paves the way for a fresh and wearable aesthetic of '90s hair. This haircut can help to give the illusion of much fuller lengths, like this style posted to Instagram by California-based hairstylist Marcela Hernandez.

The inwardly curving silhouette is created by layering, and it leaves hair looking more airy and voluminous. "A hairdresser would be lifting vertical sections of hair straight up towards the ceiling and cutting the hair with angled fingers," explains hairdresser Michael Douglas, much like in this video posted to TikTok by hairstylist Dominick Serna. "This means that you end up with shorter layers on top and longer layers on the outside, creating a concave [or rounded] shape."

In other words, each section of layered hair curves inwards, like this cut posted to Instagram by hairstylist Ryenne Snow. The shorter layers sitting on top of longer ones give the illusion of thickness and more shape, even if your hair is on the fine side. "If you were to turn the head upside down," adds Douglas, "you would see a hollowed shape. Hair would be longer on the outside and shorter on the inside." Hairstylist Kayla of Hardcore Hair demonstrates the finished result beautifully on TikTok.

As well as adding fullness to fine hair, this type of layering removes excess weight from thicker textures while maintaining length. Not only does this take effort out of washing and styling, it also promotes more dynamic movement so that hair doesn't sit heavy on the shoulders or appear triangular in shape.

Jonathan Andrew, Fudge Professional global brand ambassador, suggests that concave layers aren't exclusively for those with longer hair. "Heavily layering mid-length hair, in particular, gives a super cool, rock-chick vibe," says Andrew. Here's some TikTok inspiration, which Korean hairstylists have coined the "hush cut": wispy, curved layers with floaty bangs.

Concave layers are not reserved for straight hair. TikToker @vale.r.ia, who has curly hair, says they asked their hairstylist for concave layers to give their individual curls more definition. "She gave me four different kinds of layers throughout my hair," says Vale, the main type being concave layers, "to give them space to kind of curl on their own without being interrupted by other curls." Vale also mentions that thanks to the concave layers, their hair looks great both curly and blow-dried. Also look to hairstylist Erica Lenae Lott for more inspiration for curly concave layers.

Arrive at your hair salon armed with photos of hairstyles you love — as well as those you definitely don't like. This will ensure that you and your stylist are on the same page about the desired result. Most professionals will recognize the term "concave layers," but you can also ask for layers to enhance movement if you have fine hair, or layers to remove weight from the edges if you have thicker hair. On TikTok, The Orlando Salon also suggests asking for "round length" layers peppered with face-framing sections. They pair well with a sweeping curtain fringe, too.

Your hairdresser should address your face shape and then adapt where the concave layers start in order to suit your features. If you want the style without commitment, ask for concave layers in the bottom few inches of your hair, advises Andrew. "In this instance, you can hide them if you wish [by straightening your hair or tying it back] or choose to embrace them by flipping your hair over to one side so that they're more visible," Andrew explains. "This will lend the illusion of a big '90s blowout."

Because concave layers are relatively subtle, this is a fairly low-maintenance look. You can choose to get a trim every six to eight weeks to remove split ends and keep your face framed at the right length, but this is a style that will grow out pretty seamlessly.

Opt for styling products that work with your natural hair texture. The finish should look little undone, as though you've just run your fingers through your hair. Try Hair by Sam McKnight Cool Girl Barely There Texture Mist, for an effortless, tousled look. For a smoother but fuller finish to mimic the original '90s vibe, blow-dry hair using a large round brush.

For ease, you might like to invest in a blow-dry brush like The Drybar Double Shot Blow-Dryer Brush. R29 also rates Revlon Salon One-Step Hair Dryer and Volumizer. If you have more to spend, try Shark FlexStyle 5-in-1 Air Styler & Hair Dryer, which comes complete with two brush attachments plus auto-wrap curlers for big, bouncy waves at home.

Lastly, if you are using heated appliances to enhance your layered hairstyle, always prep your lengths with a heat protector. Fudge Professional Blow-Dry Aqua Primer, offers protection but also gives hair grip, making it easier to style and control.