Dance off! Taylor Swift gives Jessie J a run for her money during Jessie's "Bang Bang" performance.
J.Lo and Iggy closed the show with their sizzling "Booty" performance.
T.Swift was on fire during her world premiere performance of "Blank Space."
The golden goddesses are all smiles after "Bang Bang."
Tear-jerker! Bieber's ex gave an emotional performance of her new song "The Heart Wants What It Wants."
The singer performs solo at the AMAs for the first time in years!
BFF alert! The singers enjoy the show together.
Yikes! Milian dances on the rapper.
We see that booty, J.Lo!
The rockers take home the award for Favorite Alternative Rock Artist.
Grande wows the crowd while belting out "Problem," "Break Free" and "Love Me Harder."
The "Shake It Off" singer accepts the Dick Clark Award For Excellence from Diana Ross.
The boy-banders took home three AMAs!
The country crooner takes home the Favorite Country Male Artist trophy.
Lopez shows fans lots of leg!
Iggy beat out Eminem for two awards!
Lopez and Iggy drive the crowd wild with their bumping and grinding.
The blond beauty plants a kiss on one of her hunky dancers.
MORE PHOTOS: All the AMAs arrivals