"Young, Wild & Free" is a song by American rappers Snoop Dogg and Wiz Khalifa, featuring vocals from American singer-songwriter Bruno Mars. It was released on October 11, 2011, by Atlantic Records as the lead single from the soundtrack of the film, Mac & Devin Go to High School, in which the rappers star in. The track was written by Mars, Philip Lawrence, Ari Levine, Brody Brown, Snoop Dogg, and Wiz Khalifa. The track samples two other songs, "Toot It & Boot It" (2010) and "Sneakin' in the Back" (1974), songwriting credits were added for a total of seventeen. Produced by the Smeezingtons during a freestyle studio session and never meant to be heard; Aaron Bay-Shuck considered it a potential hit and asked the trio to finish it. After the song was finished, Snoop Dogg and Wiz Khalifa were added.

"Young, Wild & Free" received mixed reviews from music critics, who praised it for standing out stylistically from the rest of the soundtrack with hip-hop drums and a piano hook. Some critics praised Mars's pop-nostalgia chorus and Snoop Dogg's rap but criticized Wiz Khalifa's rap performance due to being too rough. It was commercially successful, reaching the top ten in several markets (including number seven on the Billboard Hot 100 and number six in France and Switzerland); it peaked at number two in New Zealand and number four in Australia. The single was certified six times platinum by the Recording Industry Association of America (RIAA), five times platinum by the Australian Recording Industry Association (ARIA) and by Recorded Music NZ (RMNZ).

The accompanying music video, filmed in Montclair, California in October 2011, was directed by Dylan Brown. It features Snoop Dogg and Wiz Khalifa having fun driving karts, skateboarding, and surrounded by girls at a party, interspersed with footage from Mac & Devin Go to High School. "Young, Wild & Free" was performed live several times, including on the 2012 VMA Tour and at Coachella 2012. It was also part of the 2015 Boys of Zummer (the American leg of Khalifa's tour with Fall Out Boy), Dogg's 2016 Puff Puff Pass Tour Part 2, and two collaborative tours by Snoop Dogg and Wiz Khalifa: the 2011 High School Tour and the 2016 High Road Summer Tour. The song was nominated for Best Rap Song at the 55th Annual Grammy Awards in 2013.

During an interview in the music magazine American Songwriter, Philip Lawrence said that "Young, Wild & Free" was "an after-thought" and "there's a lot of fun behind it". The song began when the Smeezingtons were experimenting in the studio, a process which usually starts when they get behind the mic and singing "until something sticks". Although the team thought "it was just a little something" which would never be heard, Aaron Bay-Shuck told them the song was a "smash" and they had to finish it. Mars later forwarded the song to Snoop Dogg. Wiz Khalifa revealed in a 2023 interview that, when Atlantic Records presented the song to him, he did not like it, but was later convinced by Snoop Dogg to record the track with him. They decided to record and returned it to Mars, who added finishing touches.

"Young, Wild & Free" was first released on October 11, 2011, by Rostrum and Atlantic Records in various countries via digital download. A clean version of the song was issued in various countries on October 21, 2011. On November 25, the single was sent for radio airplay in Italy by Warner Music Group. On December 4, 2011, the single was issued digitally in the United Kingdom. On February 2, 2012, a CD single was released with its accompanying music video in Germany, Austria and Switzerland.

"Young, Wild & Free" is a pop-rap song, composed in the key of D major with a tempo of 95 beats per minute. It differs from the G-funk style of other songs on the soundtrack, incorporating pop elements into the chorus. The song consists of hip-hop drums overlaid with a revolving, chilled "twinkling" piano hook and Mars's "sprightly" and "carefree choral hook". Its "carefree vibes" make the single "the perfect soundtrack for a Friday night with friends". Coughing is heard, implying a party vibe. The song is a weed anthem, reminiscing "hazy times" and youth: "It's like I'm 17 again/ Peach fuzz on my face/Lookin', on the case /Trying to get a hella taste", while the former in the following verses "Roll joints bigger than King Kong's fingers/ And smoke them hoes down until they're stingers." Mars's pop-soul chorus is also nostalgic: "So what, we get drunk/So what, we smoke weed/We’re just having fun/We don't care who sees/So what, we go out/That's how it's supposed to be/Living young and wild and free."

"Young, Wild & Free" was initially written by the artists alongside Lawrence, Ari Levine, and Brody Brown. Since it sampled "Toot It & Boot It" (2010) by American rapper YG and American singer Ty Dolla Sign, they received writing credits with Nye Lee, Marlon Borrow and Marquise Newman (who did additional writing). "Toot It & Boot It" had sampled "Songs in the Wind" by The Association (written by Ted Bluechel) from their 1966 album Renaissance, so Bluechel was added as a songwriter. "Young, Wild & Free"'s drum loop sampled "Sneakin' in the Back", from the 1974 album Tom Scott and The L.A. Express, and the song was re-registered with additional writing credits for Max Bennett, Larry Carlton, John Guerin, Joe Sample, and Tom Scott. The single was produced by Mars, Lawrence and Levine under their stage name, the Smeezingtons, and was engineered by Levine, Andy Drucker and Travis "Shaggy" Marshall at Levcon Studios and Paramount Recording Studios in Los Angeles and DSR in Hollywood. Levine mixed the track at Levcon Studios. It was mastered by Chris Gehringer at Sterling Sound, NYC.

The song received mixed reviews from most music critics. For Entertainment Weekly, Kyle Anderson praised its "sweet" Mars' hook; with "'song of summer' written all over it", it "could have been a graduation anthem for stoners everywhere" if it was released in May. MTV's Jenna Rubenstein gave the song a generally-positive review as more than a "reckless party jam"; the three singers are not bothered by the judgments of others, and "that's the positive, family-friendly message we're taking". Billboard magazine gave it three-and-a-half out of five stars, calling it "a haze of nostalgia". The review praised Snoop Dogg's effortless flow, but called Wiz Khalifa's delivery "forceful" and "punchy"; it "gets on top of the beat and harshes the mellow laid-back production." In a similar review, Lewis Corner of Digital Spy praised Dogg's verses and called the single "cool and addictive"; however, he found the song's "flavor" short-lived. In a negative review, Shea Serrano of LA Weekly compared the track's atmosphere to the "inside of a cloud (smoke), a celebration or idea of what some teenagers who smoke pot would like". Serrano noted, ironically, that the song's performers were neither young, wild nor free.