The song, from the upcoming James Bond movie of the same name, premiered on French radio on Thursday (October 4) before it was officially unveiled at 0:07 (UK time) today.
'Skyfall's debut comes days after a 90-second clip of the song leaked online, with the track drawing comparisons to Dame Shirley Bassey's iconic Bond themes.
Adele co-wrote 'Skyfall' with producer Paul Epworth. The duo previously collaborated on the chart-topping single 'Rolling in the Deep'.
The track's premiere marks the 50th anniversary of the release of the very first James Bond film Dr No.
Adele previously admitted that she was initially "a little hesitant" to record a Bond theme, but ultimately "fell in love" with the Skyfall script.
"It was also a lot of fun writing to a brief, something I've never done which made it exciting," she explained, adding: "I'll be back combing my hair when I'm 60 telling people I was a Bond girl back in the day I'm sure."
Photo gallery - 10 classic James Bond themes:
Dame Shirley Bassey's 'Goldfinger' and 'Diamonds Are Forever', the Carly Simon recording of 'Nobody Does It Better' and Paul McCartney's 'Live and Let Die' have become enduring pop music classics.
Skyfall - starring Daniel Craig and Javier Bardem - debuts on October 26 in the UK and on November 9 in the US.
> Shirley Bassey, Nancy Sinatra, Duran Duran: Top 10 Best Bond Themes
> 10 greatest James Bond title sequences: Casino Royale, GoldenEye, more
Watch a trailer for Skyfall below: