Amanda Michelle Seyfried ( SY-fred; born December 3, 1985) is an American actress. Known for her work in several films and television productions, she has received several awards including a Golden Globe Award and a Primetime Emmy Award with nominations for an Academy Award and two Screen Actors Guild Awards.

Born and raised in Allentown, Pennsylvania, she began modeling at age 11 and ventured into acting at 15, with recurring roles as Lucy Montgomery in the CBS soap opera As the World Turns (1999–2001) and Joni Stafford in the ABC soap opera All My Children (2003). She came to prominence for her feature film debut in the teen comedy Mean Girls (2004), and for her roles as Lilly Kane in the UPN mystery drama series Veronica Mars (2004–2006) and Sarah Henrickson in the HBO drama series Big Love (2006–2011).

Seyfried has starred in a number of films, including Mamma Mia! (2008) and its sequel Mamma Mia! Here We Go Again (2018), Jennifer's Body (2009), Dear John (2010), Letters to Juliet (2010), Red Riding Hood (2011), In Time (2011), Les Misérables (2012), A Million Ways to Die in the West (2014), Ted 2 (2015), and First Reformed (2017).

She received critical acclaim for her portrayal of Marion Davies in David Fincher's biopic Mank (2020), earning nominations for the Golden Globe Award and Academy Award for Best Supporting Actress. For her starring role as Elizabeth Holmes in the Hulu miniseries The Dropout (2022), she won the Golden Globe Award and Primetime Emmy Award for Outstanding Lead Actress. In 2022, Time named her one of the 100 most influential people in the world.