Sasha Fierce is the stage name for Beyoncé’s performance alter ego introduced around her 2003 solo career.
Beyoncé described Sasha Fierce as a more fearless, sensual, and energetic persona that emerged when she performed. She later used the concept explicitly for her 2008 double album I Am... Sasha Fierce.
That album divided its songs into two discs: I Am... presented more personal and reflective material, while Sasha Fierce emphasized the bold performance persona. Major songs associated with the latter disc include “Single Ladies (Put a Ring on It)” and “Diva.”
The name is not Beyoncé’s legal name and is not the title of a separate artist. Beyoncé later said that she had outgrown the alter ego, explaining that her confidence no longer depended on separating it from her everyday identity.