Miley Cyrus arrived in a more demure white Versace pantsuit for the AMA red carpet.
But she changed into a thigh baring two-piece covered in cats for her performance of "Wrecking Ball" that closed out the show.
Rihanna, who performed "Diamonds" during the show, went revealing on the red carpet.
But she covered up to accept the Icon Award from her mom and Bill Maher.
Katy Perry started sweet in polka dot Oscar de la Renta.
But changed into a Geisha costume for her colorful performance of "Unconditional."
Ke$ha went with a thigh-high slit and rainbow ombré hair on the red carpet.
She changed into a cowgirl costume to perform "Timber" alongside the show's host, Pitbull.
Lady Gaga arrived on a white horse “like Bianca Jagger arriving at Studio 54,” as she described it.
She stripped down to this silver bodysuit to perform "Do What U Want" with R.Kelly in the "Oval Office."
Taylor Swift, who won Artist of the Year, looked like an award herself in this shimmering gold sequined mini dress by Julien MacDonald.
Country singer Luke Bryan, who performed during the show and won Best Country Male Artist, wasn't afraid of a few sequins on his jacket.
Presenter Nicole Richie worked it in this white Emilio Pucci dress and her own House of Harlow 1960 clutch.
Christina Aguilera wore a similar long, white cut-out dress by Maria Lucia Hohan.
2 Chainz tried to out-ridiculous himself on the red carpet.
Jennifer Lopez started her Celia Cruz tribute performance in this sequined caftan.
She quickly changed into a rainbow flamenco costume.
And ended her performance in a fabulous, fringed bodysuit.
Nelly won Single of the Year and performed "Cruise" while paying tribute to the Rolling Stones.
TLC's Chilli and T-Boz reunited on the red carpet.
Lil' Mama joined the group to perform hit "Waterfalls" on-stage.
Lil' Mama wore this weird pants-cape during the performance.
"Thor" actress Jaimie Alexander kept it serious.
Heidi Klum could have used some "Project Runway" help on this Marchesa dress.
"Fashion Police" co-host Kelly Osbourne later said her dress "didn't photograph well" on the red carpet.
In her hair, she wore studded french braids.
Harry Styles also rocked quite the 'do.
Emma Roberts was swimming in her metallic dress by Lanvin.
Ciara bared almost all in this super sheer J. Mendel gown.
And the sisters Jenner showed off their midriffs before presenting during the show.
See what else you missed at the American Music Awards ...
