[6] "Youngblood" sold over five million adjusted copies worldwide within six months of release,[7][8][9] the eleventh best-selling single of all time in Australia.

Describing the song, the band's drummer Ashton Irwin stated: "We loved that new wave could be really melancholy, but also up.

[15][16] "Youngblood" received positive reviews from critics, with Jon Blistein of Rolling Stone describing the song as having a "relentless, thumping rhythm, around which 5 Seconds of Summer move between delicate verses and a booming chorus".

[18] Medium.com labelled the song as "cohesive and strong" and that it was "clear that [5 Seconds of Summer] spent their time honing a craft [that was] overlooked by stereotyping naysayers".

[29] The single did well in Britain during the summer months, from 1 June to 30 August, and ranked seventh on the Official Charts Company's Top 40 Biggest Song of the Summer 2018,[30] while the music video ranked ninth place on The Official Top 40 songs most streamed on video of 2018 so far.

[35] As of January 2022, "Youngblood" has spent over 197 consecutive weeks (over 3.5 years) in the Top 20 on the ARIA Australian Singles chart.

[10][11][37] "Youngblood" sold over five million copies within six months of release[7][38][9] and is the most streamed Australian song of all time on Apple Music.

[6][39] In February 2020, 5 Seconds of Summer were honored in the APRA AMCOS’ The 1,000,000,000 List, for "Youngblood" reaching 1 billion combined streams.

[41] The song was performed live for the first time on 20 March 2018 at the band's concert in Stockholm, Sweden as part of their sold out 5SOS III Tour.

[44] On 22 June 2018, they performed it on The Today Show's Summer Concert Series,[45] and on 28 November 2018 at the 32nd Annual ARIA Awards.

Directed by Frank Borin, the video was filmed in Tokyo and tells the story of an elderly couple in their final moments, given 24 hours to relive their youth (where they are played by Japanese artists "JOHNNY" Daigo Yamashita and Misaki Aono) which then dives into the Japanese Rockabilly culture.

[52] 5 Seconds of Summer Additional musicians On 2 November 2018, Angus & Julia Stone released a cover version of the song as a non-album single.