The UN teamed up with some of the world's most famous musicians — including Pharrell Williams, who wrote the smash hit song Happy — to develop the playlist of six songs.
Secretary-General Ban Ki Moon said in a statement that the ultimate goal of the initiative is to promote the happiness of all peoples.
"On this day, we are using the universal language of music to show solidarity with the millions of people around the world suffering from poverty, human rights abuses, humanitarian crises and the effects of environmental degradation and climate change," he said.
Ban took part himself, nominating Signed, Sealed and Delivered by Stevie Wonder for the list, though it didn't make the final cut.
A host of celebrities also contributed their picks throughout the week, including Britney Spears, who chose Prince's Kiss which made the final list.
"Can't help but get up and dance to this song. And dancing always makes me happy," she said.
Australian pop icon Cody Simpson chose the outlandish 90s hit Mambo No5 by Lou Bega, saying that "happiness comes with simple things — family and friends."
People around the world also chimed in on social media using the hashtag #HappySoundsLike.
According to the UN, the world's happiest playlist includes, in chronological order spanning multiple decades:- I Got You (I Feel Good), James Brown and His Family (1964).
- (Your Love Keeps Lifting Me) Higher and Higher, Jackie Brown (1967).
- Three Little Birds, Bob Marley and the Wailers (1977).
- Kiss, Prine and The Revolution (1986).
- Independent Woman Pt. 1, Destiny's Child (2000).
- Made to Love, John Legend (2013).