Cynthia Ann Stephanie Lauper ( LAW-pər; born June 22, 1953) is an American singer, songwriter, actress, and activist. Her album She's So Unusual (1983) was the first debut album by a female artist to achieve four top-five hits on the Billboard Hot 100—"Girls Just Want to Have Fun", "Time After Time", "She Bop", and "All Through the Night"—and earned Lauper the Best New Artist award at the 27th Annual Grammy Awards in 1985. Her success continued with the soundtrack for the motion picture The Goonies (1985) and her second record True Colors (1986). This album included the number-one single "True Colors" and "Change of Heart", which peaked at number three. Her cover of the Marvin Gaye song "What's Going On" was a moderate hit in 1987. In 1989, Lauper saw success with "I Drove All Night" and in 1993, had her first dance club hit with "That's What I Think".

Since 1983, Lauper has released eleven studio albums and participated in many other projects. In 2010, Memphis Blues became Billboard's most successful blues album of the year, remaining at number one on the Billboard Blues Albums chart for 13 consecutive weeks. In 2013, she won the Tony Award for best original score for composing the Broadway musical Kinky Boots, making her the first woman to win the category by herself. The musical was awarded five other Tonys including Tony Award for Best New Musical. In 2014, Lauper was awarded the Grammy Award for Best Musical Theater Album for the cast recording. In 2016, the West End production won Best New Musical at the Olivier Awards.

Lauper has sold over 50 million records worldwide. She has won awards at the Grammys, Emmys, Tonys, the New York's Outer Critics Circle, MTV Video Music Awards (VMAs), Billboard Awards, and American Music Awards (AMAs). An inductee into both the Songwriters Hall of Fame and the Hollywood Walk of Fame, Lauper is one of the few singers to win three of the four major American entertainment awards (EGOT). She won the inaugural Best Female Video prize at the 1984 VMAs for "Girls Just Want to Have Fun". This music video is recognized by MTV, VH1 and Rolling Stone as one of the greatest music videos of the era. She is featured in the Rock and Roll Hall of Fame's Women Who Rock exhibit. Her debut album is included in Rolling Stone's list of the 500 Greatest Albums of All Time, while "Time After Time" is included in VH1's list of the 100 Best Songs of the Past 25 years. VH1 has ranked Lauper No. 58 of the 100 Greatest Women of Rock & Roll.

Lauper is known for her distinctive image, featuring a variety of hair colors and eccentric clothing, and for her powerful and distinctive four-octave singing range. She has been celebrated for her humanitarian work, particularly as an advocate for LGBT rights in the United States. Her charitable efforts were acknowledged in 2013 when she was invited as a special guest to attend President Barack Obama's second inauguration.