Kelly Clarkson has been a major star since 2002, and if we've learned anything over these 13 years of her career, it's that she is perhaps the most dependable live pop performer of the 21st century. 

Watch her slay "Heartbeat Song" at the 2015 iheartradio-music-awards" class="autolink">iHeartRadio Music Awards and remind you just how powerful her instrument remains.