Mars' music has been noted for displaying a wide variety of styles and influences, including pop, rock, reggae,
R&B, soul, and hip hop. Although Mars has been referenced as "soft" because of his penchant for using a falsetto voice, his co-producer Philip Lawrence says, "What people don't know is there's a darker underbelly to Bruno Mars." Mars himself says, "I blame that on me singing to girls back in high school." Jon Caramanica of The New York Times called him "one of the most versatile and accessible singers in pop, with a light, soul-influenced voice that’s an easy fit in a range of styles, a universal donor."Mars was initially influenced by R&B artists such as Keith Sweat, Jodeci and R. Kelly, as well as 1950s rock 'n' roll and Motown. In high school, he began listening to classic rock groups such as The Police, Led Zeppelin, and the Beatles.All of these genres of music have influenced Mars' musical style; he observed that "It’s not easy to songs with that mixture of rock and soul and hip-hop, and there’s only a handful of them." Mars also stated that he is a fan of Alicia Keys, Jessie J, Jack White and The Saturdays. In addition, Mars claims that his work with other artists influenced his musical style, saying that "'Nothin' on You' had a Motown vibe, 'Billionaire' was a reggae acoustic guitar-driven song, though one of my favorites is the Cee-Lo [Green] song ['Fuck You!']. I don't think anyone else could've sung that song. And there's 'Just the Way You Are.' If you know my story, you know I love all different genres of music." He cites doo-wop as a major influence on his music, referring to the genre as "just straightforward love songs – so charming and simple and romantic."In addition, Mars states that growing up in Hawaii influenced his music, giving the songs a reggae sound. He explains that "In Hawaii some of the biggest radio stations are reggae. The local bands are heavily influenced by Bob Marley. That music brings people together. It's not urban music or pop music. It's just songs. That's what makes it cross over so well. The song comes first." Lyrically, many of Mars' songs have been described as "feel-good", carefree, and optimistic,however, darker subjects are addressed in songs such as "Grenade", "Liquor Store Blues", and "Talking to the Moon", which detail failed relationships and self-destructive behavior.