Here's a look at some of your favorite celebrities from back in the day.
To promote her book, Unfinished, the actress shared a photo of herself as a teenager, along with the caption, "Lean, mean and all of 17!!! #Unfinished."
Nostalgia overload! The Sister, Sister alum shared what she described as "the ultimate 90’s #TBT ?" -- and she's not wrong! Her throwback pic included a few famous TV teens of the '90s, including her sister, Tia Mowry, Sabrina the Teenage Witch's Melissa Joan Hart, Blossom's Jenna Von Oy and Full House's Jodie Sweetin and Andrea Barber. The twins were even wearing Blossom-style hats in the amazing snap!
After watching Cheer on Netflix, the model was feeling nostalgic for her days as a high school cheerleader in Snohomish, Washington, though she joked that she "sucked at cheerleading almost as much as I sucked at doing my brows." "Truly no idea how I made this team," she wrote on Instagram on Jan. 14. "The best part is they claimed there was no JV/varsity but one squad got to cheer for basketball and football and the other (mine) got volleyball and wrestling. I still remember my mat cheers though. Go fight win baby. Go fight win."
Jennifer Lopez and Salma Hayek
Hayek threw it back to 1997 to congratulate her pal on the success of Hustlers.
Khloe Kardashian and Kendall Jenner
The model shared this adorable video on Jan. 6 of her big sister giving her a bath in the kitchen sink.
Kim Kardashian West
The Keeping Up With the Kardashians star captioned this '90s pic of herself "Baby K."
Seyfried clearly looks back fondly at her days filming Mamma Mia, because she looks elated in this dancing pic from the film's wrap party in Greece in 2007.
"'Most dramatic' isn’t totally on brand but I’ll take it. #tbt," the This Is Us star wrote in December 2019 of a trophy she received as a kid.
"Christmas with one of my creators. Then and now #TBT Love you, papa ❤️," the Morning Show star captioned two sweet pics with her dad, John Aniston.
"I actually did grow up on a Christmas tree farm," the "Lover" singer shared on Dec. 5 while promoting her new holiday song, appropriately called "Christmas Tree Farm." "In a gingerbread house, deep within the yummy gummy gumdrop forest. Where, funnily enough, this song is their national anthem."
Ben Savage and Danielle Fishel
We're having a major nostalgia moment! Fishel took to Instagram on Dec. 19 to reminisce about filming a 1996 episode of Boy Meets World at Disney World with her onscreen boyfriend. "We're clearly very excited. Maybe it was because Ben was rocking a chain. Maybe it's because I just received good news via the pager on my hip. Or maybe it's because I spilled tons of food on my jeans," she wrote. "Or *maybe* it's because the airline gave me wing pins and I stuck them through the knees of my jeans. We'll never know. #tbt."
She's known for her blonde locks, but even the Big Little Lies star was surprised by her brown tresses in this kid pic. "Wait... is this my real hair color?!? ??♀️ ??♀️#tbt #1990s," she shared on Instagram in November 2019.
Larson took a look back at her Disney days with Beverley Mitchell. "Let the record show that I have been committed to transformations for my craft since 2003," the Captain Marvel star shared on Nov. 21. "Right on Track is def streaming on Disney+ so enjoy that. #tbt."
"Baby me. Old headshot from when I was 9 years old. #tbt," the Lucy in the Sky star shared on Nov. 21.
A pic unearthed from Bloom's 21st birthday, taken while he was filming Lord of the Rings, is both pure joy and confusion.
Justin and Hailey Bieber
In September 2019, the "Yummy" singer shared the first photo he and his ladylove ever took together, long before they started dating. "My wife and I :) where it all began," he wrote.
"I've always been a summer girl #tbt," the Goop founder wrote in August 2019.
"Class picture, 1977. Two years before Rapper’s Delight would be released and change EVERYTHING," the Aladdin star shared on Aug. 22.
Elizabeth Banks and Leonardo DiCaprio
The Charlie's Angels director-actress shared a behind-the-scenes shot from the 2002 set of Catch Me If You Can, writing, "#tbt I miss polaroids and I really enjoyed #onceuponatimeinhollywood #catchmeifyoucan."
In honor of Throwback Thursday, the world was graced with this pic of the former Beatle doing a handstand on a beach in Antigua in 1970. The photo was taken by the British singer-songwriter's late wife, Linda McCartney.
The funnyman's senior class photo is a true thing of '00s beauty. "'Sup ladies. I’m still rocking my carpenters and fossil watch but I’ve slipped into a Kohl’s original Superman tee. Wanna drink some Surge and play Mario cart or 007 tonight?" he joked in the January 2018 caption. "Also, I think goons has 4$ worth of kind bud he would share.” #cementtruck #ifyouknowyouknow #sideburns."
The Splitting Up Together actress took Office fans on a walk down memory lane with an adorable Throwback Thursday Polaroid snapshot from the first ever table read for NBC's iconic sitcom back in 2005. In the pic, stars David Denman, B.J. Novak, John Krasinski, Fischer, Rainn Wilson, Steve Carell and Phyllis Smith stand smiling side-by-side before getting down to some Dunder Mifflin business.
Rashida Jones and Tracee Ellis Ross
In January 2018, Jones shared a pic with her pal from 2000, marveling, "Look at these tiny babies."
In May 2017, the actress shared a photo of herself from 1978 while she was in Cannes, France.
The actress hasn't aged at all since her Dawson's Creek days! "#tbt to 1998-- when I thought I was an actual Spice Girl," she captioned the epic throwback pic on Instagram.
The Tonight Show With Jimmy Fallon host has barely changed in nearly 25 years, as evidenced when Fallon tweeted his first headshot, taken in 1992. (Well, his hair has gotten better...)
Even as a teenager, Kruger was a knockout! The Inglourious Basterds star shared a pic of her modeling when she was 15 and captioned it with a lengthy message to inspire her Instagram followers. "This is me at 15, winning the 'Look of the Year modeling award in Germany' ...HOW you might ask? I really don't know," she wrote. "Maybe that year baby face with too much makeup and crooked teeth was in style? Maybe they were playing a cruel joke on me?? Whoever picked me...thanks for the Vespa I won and the life that opened up to me!!!! All you awkward looking girls out there!!!! SOMEONE thinks you're pretty!!!"
Connie Britton and Lauren Graham
Before Gilmore Girls and Friday Night Lights, Britton and Graham were just two gals living it up in the '90s. In March 2015, Graham shared a throwback pic of the former roommates, writing, "In honor of the babely @conniebritton birthday, let's all party like its 1999! (Photo from 1999 for reference)."
Kristin Chenoweth and Idina Menzel
Before they were Glee gals, Menzel and Chenoweth were stars of the spell-binding Broadway play, Wicked. The Frozen star posted a pic of her and her longtime pal from back in the day, and may we say, this looks like a teen catalog ad from the '90s! "I always loved this shot. How beautiful is @KChenoweth here?" Menzel tweeted in December 2014.
We'd hire him! Before he was fun Andy on Parks and Recreation or a blockbuster sensation in Guardians of the Galaxy, Pratt was baring his chest hair to try to get an acting job. Sharing a Twitpic from his younger years, the actor wrote, "The name's D**chemaster McChest And this is my first headshot. You're welcome. #throwbackthursday circa 2000."
The Boston native proved he's always had plenty of Celtics pride!
Beyoncé and Solange Knowles
Dita Von Teese
Can you believe this is the brunette burlesque bombshell? The starlet posted the flashback photo in May 2014, writing, "Found this pic of me sunbathing, age 16. I still love the beach, but these days I prefer to enjoy it with sun protection or by moon-bathing in a black swimsuit paired with diamonds."
Lenny and Zoe Kravitz
How cute were the rocker and his lookalike daughter in this flashback photo?! The doting dad posted this Instagram pic, writing simply, "Sweet."
The Mad Men star shared proudly showed off an elementary school class photo, writing, "#nofilter #obviously #ilovemy9yroldself."
James Van Der Beek
The Dawson's Creek alum posted this flashback Facebook photo, writing, "#tbt Karate outfit courtesy of Mrs. Claus. Eye of the tiger courtesy of 100% unjustified swagger. My grandfather's socks? No idea what was going on there..."
Before Franco landed his role as Alien in Spring Breakers, he was already dressing the part. The Oscar nominee shared a flashback photo of himself via Instagram, writing, "YOUNG ALIEN circa 1988."
In December 2013, the Fashion Police alum captioned this Instagram pic of herself and her rocker dad Ozzy Osbourne, "Today is my Dadda's birthday! Happy birthday Dad I am so proud to be your daughter! I love you sooooo much!!!!!"
The country singer shared all of her school photos, tweeting, "Oh Goodness! Ha ha..."
The Hunger Games: Catching Fire star joked of this silly pic, "#tbt don't worry I've been properly medicated since this photo."
The Younger star looked like she could have starred in Toddlers and Tiaras! "#tbt there are so many things wrong with this," she wrote of the glam kid pic.
Before he was in costume for Magic Mike, Tatum was dressing like a cowboy!
In May 2013, Demi Moore and Bruce Willis' daughter shared a pic of herself in a Minnie Mouse costume while visiting Disneyland.
Demi Lovato shared a flashback photo of her fellow X Factor judge, sharing, "Well, well. Look at this ancient pic I found!! Same t-shirt, same middle part.. Recognize this @SimonCowell??"
Before he was a Bravo star, Andy Cohen was mowing lawns in nothing but his skivvies. The late-night host shared a flashback photo in September 2013, writing, "An Epic #ThrowbackThursday - me, a speedo, a lawnmower. Discuss....."
Lindsay Lohan shared this old-school Christmas pic of her posed with mom Dina and brother Michael.