Rolling in the Deep — Adele (2010)

Adele's scorched-earth breakup anthem remains the defining song of the early 2010s, outperforming #2 by selling over 11 million copies in the US alone and spending seven weeks at No. 1 on the Billboard Hot 100. Its raw, gospel-tinged production and seismic vocal performance set a new standard for pop ballads, becoming the best-selling digital single of 2011 with 5.8 million downloads. The track's cultural impact extended beyond charts, inspiring countless covers and cementing Adele as a generational voice — a feat no other song on this list achieved before its release.