Beyoncé used the name Sasha Fierce for an alter ego associated with her 2008 album I Am... Sasha Fierce.
She described Sasha Fierce as a more aggressive, confident stage persona that emerged during performances. The album was structured around two discs: I Am..., representing more personal material, and Sasha Fierce, representing the bolder performance character.
The alter ego became especially associated with songs such as “Single Ladies (Put a Ring on It)” and “Diva.” Beyoncé later said that she no longer needed to separate herself from the persona because she had incorporated that confidence into her everyday identity.
Sasha Fierce is not Beyoncé’s legal name, a group name, or a separate recording artist. It was a conceptual performance identity used to explain the contrast between intimate songs and highly assertive stage numbers.