It follows their previous studio album Grand (2009), which the usage of its songs in commercials and TV series and the music video for "Lessons Learned" gained the duo popularity.

Sidewalks continues Matt & Kim's basic and high-energy dance-punk synthpop style, but with a higher-fidelity sound courtesy of being recorded in professional studios instead of being self-recorded as was the case with their prior albums.

"[6][8] Aside from the professional method of recording resulting in a more high-fidelity sound, Sidewalks is consistent with Matt & Kim's previous albums in many aspects, mainly its dance punk style.

[12] None on the LP was performed live by the group; it was played on the public address system of the venue before each show began, and the duo's setlist was all of Grand.

[24] Luke O'Neil of The Boston Globe and Chris Coplan of No Ripcord praised Sidewalks as a "street-savvy" and "likable" presentation of the confusion of youth.

[6][25] The album was also called "therapy you can spaz out to" by J. Edward Keyes of Rolling Stone, who considered its "pervasive optimism" its greatest feature.

[10] On the other hand, NME's Ben Hewitt was turned off by its "vomit-inducing" and "sickly" sound, "chart-pap melodies", and "sodden clichés", and joked Johnson's vocals "wavers unconvincingly like an exasperated Dad failing to assert their authority".

Detractors felt it watered down the duo's characteristic amateur punk hardiness and rebellion, most displayed in their live performances, in favor of a pop sound.

[8] However, some reviewers felt the hi-fi production improved Matt & Kim's sound and that their perceived frantic punk persona was still prevalent enough to be enjoyable.

"[20] Chris Martins of Spin felt its larger sound and increased emphasis on choruses better reflected the "in-person oomph" of their live performances, and that its "best tracks trade Kim's punk drumming for handclaps, sleigh bells, and bassy kicks".

[22] All tracks are written by Matt Johnson and Kim Schifino and produced by Ben H. Allen and Oliver StrausCredits from the liner notes and Billboard.