Is it just us or does it seem like only yesterday we were rocking out to Katy Perry's brand-new single "I Kissed a Girl"? Over the last nine years, Katy (who's turning 33 on Oct. 25, 2017) has reinvented herself time and time again, often mixing her newest looks with her latest music (like her current platinum blonde pixie cut that preceded the June 2017 release of her latest album, "Witness"). In honor of Katy's birthday and ever-changing style, Wonderwall.com is taking a look at all our favorite pop stars to see how their appearances have changed since they first launched their music careers. Keep reading to see their unbelievable transformations…
While most of us didn't know the name Katy Perry until 2008, it turns out she was already making music back in 2001 — under her real name, Katy Hudson. Seen here at age 18 in 2002, Katy had released a self-titled debut album of Christian music a year earlier. Rocking short, dark hair, a makeup-free face and a simple T-shirt, Katy proved that without even trying, she's always been the prettiest girl in the room.
Justin Bieber (seen here in August 2017) seems to have always been a tattooed bad boy with super-casual style. Long before "Despacito," Justin had a totally different look… and it definitely makes us wanna sing "Baby."
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If you've always had a thing for Justin Bieber, you might feel a little creepy at how totally young he was (and looked!) back when he first started his career. This picture, taken on Sept. 1, 2009, came barely three months after his debut single, "One Time," hit the airwaves. Even back then, the Biebs kept his arms crossed in pictures, but he was working a totally different hairstyle (and a major baby face).
Beautiful Ariana Grande is all hair, awesome vocals and sex appeal these days, but back in 2010 when she was brand new in Hollywood, she looked completely different…
Yes, still cute, but we can hardly recognize Ariana Grande in this March 2010 picture. At just 16, Ariana (who played Cat Valentine in the Nickelodeon series "Victorious") had more of a fashion-forward high school vibe going than one of a sultry singer. It would be three more years before Ariana would release her debut album, "Yours Truly," in 2013 and transform into the chart-topping pop star we know today.
He's a husband and a father… he can sing, he can dance, he can act… and he's just really, really hot. Has there ever been a time when Justin Timberlake (seen here at the 2017 Academy Awards) wasn't the sexiest guy ever? Short answer: No. You won't believe how adorable Justin looked in the early '90s when he landed his first major gig…
How cute was Justin Timberlake in 1994 when he starred on "The All New Mickey Mouse Club" alongside some other future Hollywood heavy-hitters like Ryan Gosling, Christina Aguilera and even his former flame, Britney Spears?! His perfectly coiffed blonde curls and playful smile make us wish we were back in junior high.
Edgy Miley Cyrus has been sporting a more toned-down look in 2017. Maybe it's her on-again romance with hottie Liam Hemsworth (that's Thor's little brother, btw) that's giving her a more grown-up glow. But before her wild-style phase in recent years, which often included flashes of her very prominent tongue (and other body parts), Miley was the sweetest-looking little girl there ever was…
We really just want to pinch Miley Cyrus's adorable little cheeks in this 2006 picture. At the time, she was on the cusp of landing the role that would make her a star — the title character on the Disney Channel series "Hannah Montana."
Yes, Bruno Mars makes us feel like "24K Magic" when we hear his sultry voice on the radio, but was he always a smoking-hot singer with cheekbones we could write poetry about?
Answer: Yes. Handsome Bruno Mars hasn't changed all that much since he debuted on the airwaves in 2010 with "Just the Way You Are." Maybe he once rocked an Elvis-inspired hairdo and a less-defined fashion sense, but even back then, he still knew how to work it.
We'd bet money on the fact that Colombian crossover singer and mom of two Shakira has never once had an awkward, ugly duckling phase. Whether you've been her fan for decades or just this year with the release of her latest album, "El Dorado" (can we gush about her song "Me Enamoré" featuring her hot soccer-star husband, Gerard Piqué?), you've probably noticed Shakira is so beautiful, it hurts.
This is Shakira in 1992 when she was just 15 years old. The young (and beautiful) singer had already released her first album, "Magia," a year earlier and was working on her second album, "Peligro," which would debut in March 1993. She rocked her naturally black hair until around 1999, when she briefly went red, before settling on her trademark wavy blonde locks in 2000.
To be fair, British singer Sam Smith hasn't been a pop star for very long — meaning his looks haven't changed much over the last few years. Still, his chart reign has been fast and fierce (and we're loving every minute of it).
Seen here in 2013, shortly after the U.K. release of his hit single "Lay Me Down," 21-year-old Sam Smith had a more youthful aura with some seriously cherubic cheeks. Something about his leather coat and fade haircut make us think of a modern James Dean (who can sing like Adele).
It's hard to believe there was a time when Jennifer Lopez wasn't an icon of style. Seen here in September 2017 — just three months after releasing her hit Spanish-language single "Ni Tú Ni Yo" with Gente de Zona — it's clear J.Lo knows how to dress (or undress) every curve on her glorious figure. How is she the mother of twins?!
Before her debut album "On the 6" was released in 1999 and before she starred in "Selena" in 1997, Jennifer Lopez was one of the flyest (fly girls that is) on the hit sketch comedy show "In Living Color." Seen here in a 1992 portfolio shoot, Jenny from the block might have started out as a dancer with an affinity for a bold lip, slicked-back hair and shoulder pads (hey, it was the '90s), but she always also had a certain something that made people take notice.
Taylor Swift (seen here performing in Houston in 2017) might have that red lip classic thing that we like, but she's also not afraid to play with her style, often mixing a bit of sweet with a whole lot of sass and turning it into something uniquely Taylor. She wasn't always a fashion-forward princess of pop, though…
Pictured here in October 2006 (when she was only 16 years old), young country music singer Taylor Swift was just days away from releasing her self-titled debut album. Her look was (as expected) more understated and even a bit "cutesie" with perfect ringlets and coral lips.
Ed Sheeran is our favorite Grammy-winning ginger and we don't care who knows it. The singer-songwriter's face gained a new scar in January 2017 while hanging out with Princess Beatrice at a party in Windsor. Apparently, Ed accidentally got his face slashed with a sword by the horrified princess who was playfully "knighting" him. The singer was quick to defend her, claiming it was a "rowdy party." Wait till you see what Ed looked like before the scar — and before he was a legend in the music business.
Ed Sheeran was just days away from turning 19 in this picture (taken in 2010) and on the verge of releasing his fifth extended play independent album, "Loose Change" — the compilation that would finally get him recognized in the music world. It also held his first No. 1 song, "The A Team." At the time, Ed clearly didn't care much about polishing his look. Did no one at the BBC (where he was performing that day) have a hairbrush?
We don't call Beyonce Queen Bey for nothing. Just months after giving birth to twins in 2017, this stylish pop star flaunted her unbelievable figure in a skin-tight emerald gown with a playful plum fur wrap. The 22-time Grammy winner continues to evolve, both in her music and her style.
We can't help but wonder if Beyonce, seen here in 1998 when she was just a week shy of turning 17, knew that she was on track to become one of the biggest deals in music ever? At the time, Bey was a member of Destiny's Child, and while she hadn't yet developed her signature style, she clearly had a taste for fashion with some flair.
Hasn't Nick Jonas always been a super-sexy solo recording artist churning out hit songs like "Jealous" and "Find You"? Seen here at the 2017 Grammys, it's hard to remember a time when Nick didn't make us weak in the knees…
It's almost jarring to see 13-year-old Nick Jonas back in 2006 when he was still a member of The Jonas Brothers — a boy band that also included older siblings Joe Jonas and Kevin Jonas. He was totally adorable (we won't lie), but he still had years to go before he would step out on his own and become the super-sleek, ultra-sexy solo artist we know him as today.
Radiant Gwen Stefani (seen here in 2017) has always pushed the boundaries of style. Known for incorporating fashion elements from around the world (remember her Harajuku days?), Gwen has shown us that being an artist doesn't just apply to the music.
When Gwen Stefani first hit the music scene, she was a member of the pop-rock band No Doubt. Seen here in 1996 (four months shy of turning 27), Gwen was rocking a much harsher look with her heavily lined eyes, bold lip, messy hair and decorative crystal bindi. She definitely fit the wild look of the '90s but already showed hints of having a powerfully individual sense of style.