[4] It has been described as an upbeat disco-pop song[1] with elements of funk, soul, and bubblegum pop, and takes influence from 1970s music—it features snapping handclaps, echoing synths, and celebratory horns.

Upon release, "Dynamite" received positive reviews from music critics, with praise towards its catchiness and broadly appealing retro sound.

[20][21] The track features a funky bassline accompanied by vocal harmonies, falsetto hooks and a disco rhythm that is "ready-made for the dancefloor.

[11] The song opens with a snippet of the chorus, where Jungkook sings, "'Cause I, I, I'm in the stars tonight/ So watch me bring the fire and set the night alight."

[22] Craig Jenkins of Vulture compared the horns in the chorus to that of Neon Genesis Evangelion's theme song, "A Cruel Angel's Thesis" (1995) and described "Dynamite" as "a vehicle expressly designed to break through the stratosphere", noting its similarity in genre to the handful of other disco-influenced songs that reached number one on the US Billboard Hot 100 earlier that year (namely Doja Cat's "Say So", Harry Styles' "Watermelon Sugar", and Lady Gaga and Ariana Grande's "Rain on Me").

"[26] In an interview with Zane Lowe of Apple Music, RM said the song is "made of positive vibes, energy, hope, love, the purity, everything.

[21][25][24] Alyssa Bailey of Elle interpreted the lyrics as "a much-needed burst of joy and invitation to join them, dance, and be a light, even when the world seems a little dark".

Discussing the song, which was one of their most heavily promoted releases thus far, the band said that "due to COVID-19, people around the world have been going through tough times and we wanted to share some positive energy with our fans".

[35] The following day, pre-orders went live for 7-inch and cassette editions of the song, as well as the digital single and its instrumental for US customers; the physical versions sold out within an hour.

[43] "Dynamite" was met with mostly positive reviews from music critics upon release, with emphasis on its catchiness and broadly appealing retro sound.

"[24] Similarly, Jenkins found the track's "cute, catchy, unassuming mass entertainment" akin to "Uptown Funk" and Katy Perry's songs from her 2010 album, Teenage Dream.

[23] Reviewing for the Los Angeles Times, Laura Zornosa opined that the song is "soaked in color and nostalgia" and acclaimed it for having "all the ingredients for a summer success" by fusing "the novelty of 'Old Town Road' with the international flair of 'I Like It' and 'Despacito' and all the sunny hype of 'Can't Stop the Feeling!'"

[48] Patrick Hosken of MTV praised the track and wrote, "the song itself is a blockbuster, not because it's overstuffed with ideas but because it's light and airy and, crucially, feels like summer.

"[49] Rhian Daly of NME stated the song "mines the bright, infectious sounds of disco to get its joyful energy across, sticking to the genre's tradition of serving as a form of escapism when life gets hard.

"[13] Aamina Khan of Vogue compared it to their previous single "Boy with Luv" (2019) and praised the pop sound calling it "a welcome summer wind-down.

"[11] Robin Murray of Clash cited it as an "up-front return" and highlighted the "glossy" production, adding that it "showcases each member's ability, bringing it all together as a seamless whole.

"[22] P. Claire Dodson of Teen Vogue regarded the track as a "lighthearted, energetic pop that proves yet again the dexterity they possess with sound and aesthetic" which was "precisely for that energy" and viewed it as "a shift from the overall arc" of their previous album, Map of the Soul: 7.

[19] On August 20, a live countdown started at 11:30 PM EST on Big Hit's YouTube channel, half an hour before the music video's release.

[80] It became the fastest music video by a Korean group to achieve to 800 and 900 million views,[81] when it crossed the former five months after release in January 2021,[82] and the latter 40 days later.

[84][85] A B-side version of the music video, filmed on the same set as the original "but with different angles and a few amusing bloopers", was released on August 24 and showed "[BTS] having fun together in joyful vibes".

[90][91][94] "Dynamite" was the best-performing song of September and October 2020 in South Korea, based on digital sales, streaming, and background music (instrumental track) downloads.

[102] In the United States, "Dynamite" debuted atop the Billboard Hot 100, becoming BTS' first number-one single there and their fourth top-ten entry.

[105] Supported by subsequent "Poolside", "Tropical", EDM, and acoustic remixes, as well as an instrumental version, "Dynamite" sold a further 182,000 units in its second week and remained atop the Hot 100.

[107] "Dynamite" entered the Pop Songs chart at number 30 on the issue dated August 29, 2020, becoming the band's sixth entry on the ranking.

On the week of November 7, it reached the ninth position, becoming their first top ten on the chart, and also the highest-charting song by a Korean act, besting Psy's "Gangnam Style" (2012).

[113][114] The single became BTS's fourth to achieve platinum status in the US and their first to receive double-platinum certification from the Recording Industry Association of America (RIAA), doing so on March 17.

[116][117] On the Hot 100 issue of the same date, the single spent its 31st consecutive week inside the top 50,[118] tying with "Gangnam Style" as the longest-charting songs by a Korean artist there.

U.S. which tracks the same metrics excluding the US, "Dynamite" launched at number two on both the charts, blocked from reaching the top spot by Cardi B's "WAP" and Maluma's "Hawai", respectively.

[127] In March 2021, the International Federation of the Phonographic Industry (IFPI) published its annual top-10 charts for the previous year and listed "Dynamite" as the 10th best-selling digital single of 2020 globally, having amassed 1.28 billion subscription stream equivalents worldwide in less than five months.

[267] The song won five consecutive weekly Melon Popularity awards from September 9–28,[268] and also achieved a record 32 music show wins in South Korea.