Hold the phone: Taylor Momsen turns 18 TODAY. The Pretty Reckless singer and former Gossip Girl bad gal is finally a grown-up and there's PUHLENTY to celebrate. Pantsless of course. Taylor's come a long way, baby. Sure, her clothing has remained constant since she started exclusively wearing black platform boots and errant leather scraps and a cape of wavy/dyed/dreadlocked blonde hair, but one thing has changed so dramatically we'd be remiss not to mention it. With each platinum extension and step toward near-nudity, Taylor has never forgotten what is most important to a fledgling rocker—black eyeliner.

Rock and roll doesn't mean a "lovely smoky eye," it means MAKEUP DRIPPING DOWN YOUR FACE AND MASCARA SMEARED ON PEOPLE STANDING NEXT TO YOU. Let's face it: Momsen is a rock star, and 18 years old is prime time for a heavy hand. To celebrate, we've created a retrospective with an accompanying "Eyeliner Scale" to judge progress where 0 is baby-faced freshness and 10 is looking into the deep black of insanity. So Taylor, happy birthday to you and your evolution in kohl. Mazel!

EYELINER SCALE: 0

Taylor Momsen at Disney's Toontown Online Takes Hollywood in 2005.

Photo: WireImage

EYELINER SCALE: .5

Taylor Momsen at NikeID Studio opening in 2007.

Photo: Film Magic

EYELINER SCALE: 1

"Gossip Girl" at the Paley Fest, 2008.

Photo: FilmMagic

EYELINER SCALE: 1.5

Taylor Momsen at the "Entertainment Weekly"/Vavoom Upfront Party in 2008.

Photo: WireImage

EYELINER SCALE: 2.5

Henri Bendel celebrates new season of "Gossip Girl," 2008.

Photo: FilmMagic

EYELINER SCALE: 3

Taylor Momsen on the "Gossip Girl" set, 2008.

Photo: FilmMagic

EYELINER SCALE: 3.1

Taylor Momsen at the launch of Carrera Vintage Sunglasses, 2009.

Photo: Getty Images

EYELINER SCALE: 3.8

Taylor Momsen at the Anna Sui for Target pop-up store, 2009.

Photo: WireImage

EYELINER SCALE: 4.5

Taylor Momsen at a Clinique event, 2009.

Photo: FilmMagic

EYELINER SCALE: 5.5

Taylor Momsen at the Whitney Gala, 2009.

Photo: WireImage

EYELINER SCALE: 6

Taylor Momsen at the G-Star Raw S/S 2010 Fashion Week presentation.

Photo: WireImage

EYELINER SCALE: 7

Taylor Momsen at "Good Day New York," 2010.

Photo: FilmMagic

EYELINER SCALE: 8.2

Taylor Momsen at the 2010 European MTV Movie Awards.

Photo: WireImage

EYELINER SCALE: 9.1

23rd Annual Revolver Golden God Awards with Pretty Reckless, in 2011.

Photo: WireImage

EYELINER SCALE: ONE MILLION

At the Hard Rock Hotel in 2011.

Photo: FilmMagic