Celebrities are getting in on the #10YearChallenge fun, sharing old photos of themselves on Instagram.

The challenge has taken social media by storm, with folks sharing photos from 2009 side-by-side with new pictures from 2019. The craze has reached Hollywood and fans are delighted.

Stars like Janet Jackson, Ellen DeGeneres, Jessica Biel, Viola Davis and more have posted their own ten year challenge pictures, collecting thousands of likes. Others, like Gabrielle Union, went the extra mile, sharing a photo from ten years ago along with one from ten years before that.

Not everyone is up to the challenge, however. Demi Lovato weighed in on it online, revealing that she won't be participating. The "Confident" singer said she's "too busy" in the present to revisit her past.

Check out your favorite star's #10YearChallenge photos:

Janet Jackson

Ellen DeGeneres

Jessica Biel

Chance the Rapper

Viola Davis

Gabrielle Union

Amy Schumer

Kate Beckinsale

Jerry O'Connell

Candace Cameron Bure

Tyra Banks

Elizabeth Banks

Busy Phillips

Nicole "Snooki" Polizzi

Chrissy Teigen

Trevor Noah

Lori Loughlin

Steve Aoki

Padma Lakshmi

Jennifer Lopez

Alison Brie

Nicki Minaj

Christina Aguilera

Sonequa Martin-Green

Brie Larson

Caitlyn Jenner

Madonna

Reese Witherspoon

Jesse Tyler Ferguson

Ryan Seacrest

Kate Hudson

Isla Fisher

Kelly Ripa

Diplo

Robert Irwin