Katheryn Elizabeth Hudson (born October 25, 1984), known professionally as Katy Perry, is an American singer, songwriter, and television personality. She is one of the best-selling music artists in history, having sold over 151 million records worldwide. Perry is known for her influence on pop music and her camp style, being dubbed the "Queen of Camp" by Vogue and Rolling Stone. The world's highest-paid female musician in 2015 and 2018, Billboard named her one of the greatest pop stars of the 21st century.

At 16, Perry released a gospel album titled Katy Hudson (2001) under Red Hill Records, which was unsuccessful. She moved to Los Angeles at 17 to venture into secular music, and later adopted her stage name from her mother's maiden name. Perry recorded an album while signed to Columbia Records, but was dropped before signing to Capitol Records. She rose to fame with One of the Boys (2008), a pop rock album containing her debut single "I Kissed a Girl" and follow-up single "Hot n Cold", which reached number one and three on the U.S. Billboard Hot 100 respectively.

Perry's disco-influenced pop record Teenage Dream (2010) became the only album by a female artist to spawn five U.S. number-one singles: "California Gurls", "Teenage Dream", "Firework", "E.T.", and "Last Friday Night (T.G.I.F.)". Its reissue, subtitled The Complete Confection (2012), produced the U.S. number-one single "Part of Me". The dance-inspired Prism (2013) spawned two U.S. number-one singles, "Roar" and "Dark Horse", with their respective music videos making Perry the first artist to have multiple videos reach one billion views on Vevo and YouTube. Her following albums—Witness (2017), Smile (2020) and 143 (2024)—were released to varying critical and commercial success.

Four of Perry's songs have received diamond certifications from the Recording Industry Association of America (RIAA). Her accolades include a Billboard Spotlight Award, 19 Guinness World Records, five Billboard Music Awards, five American Music Awards, a Brit Award, a Juno Award, and the Michael Jackson Video Vanguard Award. Outside of music, she released an autobiographical documentary titled Katy Perry: Part of Me in 2012, voiced Smurfette in The Smurfs film series (2011–2013), and launched her own shoe line Katy Perry Collections in 2017. Perry served as a judge on American Idol from the sixteenth season in 2018 to the twenty-second season in 2024. With an estimated net worth of $360 million, she is among the world's wealthiest musicians.

Katheryn Elizabeth Hudson was born on October 25, 1984, in Santa Barbara, California, to Pentecostal pastors Mary Christine (née Perry) and Maurice Keith Hudson. Both of her parents turned to religion after a "wild youth". Perry has English, German, Irish, and Portuguese ancestry. Through her mother, she is a niece of film director Frank Perry. She has a younger brother named David, who is also a singer, and an older sister, Angela.

From ages three to 11, Perry frequently moved across the country as her very strict parents set up churches before settling again in Santa Barbara. Growing up, she attended religious schools and camps, including Paradise Valley Christian School in Arizona and Santa Barbara Christian School in California during her elementary years. The family struggled financially, sometimes using food stamps and eating food from the food bank which also fed the congregation at her parents' church.

Growing up, Perry and her siblings were not allowed to eat the cereal Lucky Charms as the word "luck" reminded their mother of Lucifer, and were also required to call deviled eggs "angeled eggs". Perry primarily listened to gospel music, as secular music was generally discouraged in the family's home. She discovered popular music through CDs she smuggled home from her friends. Perry later recalled a story about how a friend of hers played "You Oughta Know" by Alanis Morissette, which influenced her songwriting and singing.

While not strictly identifying as religious, she has stated, "I pray all the time – for self-control, for humility." Wanting to be like her sister Angela, Perry began singing by practicing with her sister's cassette tapes. She performed the tracks in front of her parents, who let her take vocal lessons like Angela was doing at the time. She began training at age nine; she was also incorporated into her parents' ministry, singing in church from ages nine to 17. At 13, Perry was given her first guitar for her birthday, and publicly performed songs she wrote.