Stefani Joanne Angelina Germanotta ( STEF-ən-ee JUR-mə-NOT-ə; born March 28, 1986), known professionally as Lady Gaga, is an American singer-songwriter and actress. She is known for reinventing her image and showcasing versatility in entertainment. Gaga started performing as a teenager by singing at open mic nights and acting in school plays. She studied at Collaborative Arts Project 21 before leaving to pursue a music career. After a contract cancellation by Def Jam Recordings, Gaga worked as a songwriter for Sony/ATV Music Publishing. In 2007, she signed with Interscope Records and KonLive Distribution. Her breakthrough came the following year with her debut studio album, The Fame, and its number-one singles "Just Dance" and "Poker Face". The album was later reissued along with The Fame Monster (2009), which yielded the successful singles "Bad Romance", "Alejandro" and "Telephone".
Gaga's five succeeding albums all debuted atop the US Billboard 200. Her second full-length album, Born This Way (2011), explored electronic rock and techno-pop and sold more than one million copies in the first week. Its title track became the fastest-selling song on the iTunes Store, with over one million downloads in less than a week. Following her EDM-influenced third album, Artpop (2013), she pursued jazz on the album Cheek to Cheek (2014) with Tony Bennett, and delved into soft rock on the album Joanne (2016). She ventured into acting, winning awards for her leading roles in the miniseries American Horror Story: Hotel (2015–2016) and the musical film A Star Is Born (2018). Her contributions to the latter's soundtrack, which spawned the chart-topping single "Shallow", made her the first woman to win an Academy Award, BAFTA Award, Golden Globe Award and Grammy Award in one year. Gaga returned to dance-pop with her sixth studio album, Chromatica (2020), which yielded the number-one single "Rain on Me", and released her second and final collaborative album with Bennett, Love for Sale (2021). She followed this with starring roles in the films House of Gucci (2021) and Joker: Folie à Deux (2024).
Having sold an estimated 170 million records, Gaga is one of the world's best selling music artists and the only female artist to achieve four singles each selling at least 10 million copies globally. Her accolades include 13 Grammy Awards, 2 Golden Globe Awards, 18 MTV Video Music Awards, awards from the Songwriters Hall of Fame and the Council of Fashion Designers of America, and recognition as Billboard's Artist of the Year (2010) and Woman of the Year (2015). She has also been included in several Forbes power rankings and ranked fourth on VH1's Greatest Women in Music (2012). Time named Gaga one of the 100 most influential people in the world in 2010 and 2019 and placed her on their All-Time 100 Fashion Icons list. Gaga's philanthropy and activism focus on mental health awareness and LGBT rights; she has her own non-profit organization, the Born This Way Foundation, which supports the wellness of young people. Her business ventures include Haus Labs, a vegan cosmetics brand launched in 2019.