BOL4 (), also known as Bolbbalgan4 or , is a South Korean musical act formed by Shofar Music in 2016. They appeared on Superstar K6 in 2014 before signing a contract with their current agency. BOL4 was originally a duo consisting of Ahn Ji-young and Woo Ji-yoon. They debuted with the single "Fight Day" from the mini-album Red Ickle on April 22, 2016.
The duo went on a temporary hiatus due to Ahn's music classes requirements in the first half of 2018. BOL4 signed with King Records and debuted in Japan on June 5, 2019, with the mini-album Red Planet (Japan Edition).
On April 2, 2020, Shofar Music announced that Woo Ji-yoon had left the duo and that Ahn Ji-young will continue to promote as BOL4. In April 2025, BOL4 parted ways with their agency after 10 years of working with them.
Name The group's name in English comes from the first syllable of the Korean word ("puberty"), which is pronounced the same as the Sino-Korean numeral four ().
Formation
Ahn Ji-young and Woo Ji-yoon were both raised in Yeongju, North Gyeongsang Province, and were classmates. They had previously competed on Superstar K 6 in 2014. Since they were young, they had dreamed of becoming singers. The name of their duo was chosen because they wanted to make the kind of pure, honest music that can only be found in adolescence. Woo portrays the "blushing" part of the name because she is often shy, while Ahn portrays "youth" because she acts like an adolescent girl.
Members Current Ahn Ji-young () – main vocals
Former Woo Ji-yoon () – guitar, rapping, backing vocals
Discography Studio albums Title Album details Peak chart positions Sales KORGaon Album Chart: Red PlanetReleased: August 29, 2016 Label: Shofar Music Formats: CD, digital download, streaming 15KOR: 25,646Cumulative sales of Red Planet:
Extended plays Title EP details Peak chart positions Sales KORCircle (formerly Gaon) Album Chart: JPN JPN HotBillboard Japan Hot Albums: USWorldBillboard World Albums: Korean Red IckleReleased: April 22, 2016 Label: Shofar Music Formats: CD, digital download, streaming 30 — — —KOR: 659 Red Diary Page.1Released: September 28, 2017 Label: Shofar Music Formats: CD, digital download, streaming 7 — — 9KOR: 13,277Cumulative sales of Red Diary Page.1: Red Diary Page.2Released: May 25, 2018 Label: Shofar Music Formats: CD, digital download, streaming 5 — — —KOR: 8,375 Puberty Book I BomReleased: April 2, 2019 Label: Shofar Music Formats: CD, digital download, streaming 16 — — —KOR: 5,689 Two FiveReleased: September 10, 2019 Label: Shofar Music Formats: CD, digital download, streaming 6 — — —KOR: 5,162 Puberty Book II PumReleased: May 13, 2020 Label: Shofar Music Formats: CD, digital download, streaming 8 — — —KOR: 5,536 SeoulReleased: April 20, 2022 Label: Shofar Music Formats: CD, digital download, streaming 26 — — — Love.zip ()Released: April 16, 2023 Label: Shofar Music Formats: CD, digital download, streaming 42 — — — KOR: 5,074 Merry Go RoundReleased: December 12, 2023 Label: Shofar Music Formats: CD, digital download, streaming 22 — — — KOR: 3,788 Japanese Red Planet (Japan Edition)Released: June 5, 2019 Label: King Records Formats: CD, digital download, streaming — 41 63 —JPN: 1,130 "—" denotes releases that did not chart or were not released in that region.
Singles As lead artist Title Year Peak chart positions Sales Certifications Album KORCircle (formerly Gaon) Digital Chart:KORSongsPeak chart positions on Billboards K-pop Hot 100 and South Korea Songs: JPN Korean "Fight Day" ()2016 — —KOR: 16,260 rowspan="7" Red Ickle "Galaxy" () 2 36 —KOR: 2,716,160Cumulative sales of "Let the Universe": Red Planet "Hard to Love" () 12 46 —KOR: 2,500,000 "Tell Me You Love Me" () 2 19 —KOR: 2,500,000 "Some" () 2017 1 1 —KOR: 2,500,000 Red Diary Page.1 "To My Youth" () 3 2 —KOR: 2,500,000 "#First Love" () 2018 2 2 — "Travel" () 1 1 —KOR: 2,500,000KMCA: Platinum Red Diary Page.2 "Wind" () 20 36 — rowspan="21" rowspan="2" "Dejavu" 21 30 —Red Diary 'Hidden Track''' |- ! scope="row" | "Bom" () | rowspan="4" | 2019 | 1 || 4 || — | KMCA: Platinum | rowspan="3" | Puberty Book I Bom|- ! scope="row" | "Stars Over Me" () | 4 || 10 || — | rowspan="18" |- ! scope="row" | "Mermaid" | 22 || 30 || — |- ! scope="row" | "Workaholic" () | 1 || 2 || — | Two Five|- ! scope="row" | "Leo" () | rowspan="4"| 2020 | 2 || 3 || — | rowspan="2"| Puberty Book II Pum|- ! scope="row" | "Hug" () | 30 || 19 || — |- ! scope="row" | "Atlantis Princess" () | 36 || 26 || — | Our Beloved BoA #2 – SM Station|- ! scope="row" | "Dancing Cartoon" | 49 || — || — | Filmlet|- ! scope="row" | "Butterfly Effect" () | rowspan="2" | 2021 | 23 || 37 || — | rowspan="2" | Butterfly Effect|- ! scope="row" | "Space" () | 32 || 14 || — |- ! scope="row" | "Seoul" | 2022 | 18 || 99 || — | Seoul|- ! scope="row" | "Friend the End" | rowspan="4" | 2023 | 15 || — || — | rowspan="2" | Love.zip|- ! scope="row" | "Chase Love Hard" | 36 || — || — |- ! scope="row" | "Someday" () | 84 || — || —
! scope="row" | "Snowball" () | 76 || — || — | Merry Go Round|- ! scope="row"| "Lips" | rowspan="2" | 2024 | 102 || — || — | rowspan="4" |- ! scope="row"| "Bloom" | 110 || — || — |- ! scope="row"| "Find You" | rowspan="2"| 2026 | — || — || — |- ! scope="row"| "Please Summer!" () | 9 || — || — |- ! colspan="9" | Japanese |- ! scope="row" | "Uchū o Ageru" () | rowspan="3" | 2019 | — || — || — | rowspan="3" | rowspan="5" | Red Planet (Japan Edition)'' "Watashi no Shishunki e" () — — — rowspan="4" "Some" — — "Love" 2020 — — 48 JPN: 720 "Watashi dake, Haru" () — — — "—" denotes releases that did not chart or were not released in that region.
Collaborations Title Year Peak chart positions Sales Album KORGaon Digital Chart:KORHotKpop Hot 100: The Kpop Hot 100 was discontinued beginning with the July 16, 2014 issue date. On the issue dated May 29 – June 4, 2017, the chart was re-established. "Romantic Wish" 2016 — rowspan="4" "We Loved" () 2017 1 4KOR: 2,500,000 "New York" 2019 107 — rowspan="2" "Awkward" () 2020 116 — "—" denotes releases that did not chart or were not released in that region.
As featured artist Title Year Peak chart positions Sales Album KORGaon Digital Chart:KORHotKpop Hot 100: The Kpop Hot 100 was discontinued beginning with the July 16, 2014 issue date. On the issue dated May 29 – June 4, 2017, the chart was re-established. "Lost Without You" () 2017 5 77KOR: 1,012,764 Love Is a Dog from Hell "Mohae" () 5 23KOR: 260,140Cumulative sales of "Mohae": rowspan="2" "Hurry Up" 2018 — — rowspan="2" "Be Your Christmas" — — Be Your Christmas "—" denotes releases that did not chart or were not released in that region.
Soundtrack appearances Title Year Peak chart positions Sales Album KORGaon Digital Chart:KORHotKpop Hot 100: The Kpop Hot 100 was discontinued beginning with the July 16, 2014 issue date. On the issue dated May 29 – June 4, 2017, the chart was re-established. "Hidden Path" () 2014 60 rowspan="3" KOR: 55,979 Misaeng OST Part 4 "Dream" () 2016 54KOR: 47,657Cumulative sales of "Dream": Hwarang OST Part 3 "Hello" — Lost Tale Mobile Game OST "You and I From the Beginning" () 2017 3 10KOR: 2,500,000 The Emperor: Owner of the Mask OST Part 2 "My Trouble" 2018 48 52 rowspan="3" Why: The Real Reason You Got Dumped OST Part 1 "Love Letter" 2020 95 rowspan="2" Start-Up OST Part 12 "Someday" 2026 —Sold Out on You OST Part 6 "—" denotes releases that did not chart or were not released in that region.
Other charted songs Title Year Peak chart positions Sales Album KORGaon Digital Chart:KORHotKpop Hot 100: The Kpop Hot 100 was discontinued beginning with the July 16, 2014 issue date. On the issue dated May 29 – June 4, 2017, the chart was re-established."Grumpy" () 2016 38 94KOR: 1,052,943Cumulative sales of "Grumpy": Red Ickle "You(=I)" 40 74KOR: 1,371,749Cumulative sales of "You (=I))": Red Planet "When You Fall in Love" () 78 rowspan="2" KOR: 66,307 "Grumpy" () 83KOR: 69,098Cumulative sales of "Grumpy": "Blue" 2017 5 7KOR: 757,087 Red Diary Page.1 "Fix Me" () 11 11KOR: 467,335Cumulative sales of "Fix Me": "Imagine" () 12 12KOR: 399,631Cumulative sales of "Imagine": "Lonely" 2018 24 40 rowspan="23" Red Diary Page.2 "Starlight" () 34 43 "Dear, Teddy Bear" () 42 52 "Clip" 65 66 "6 o'clock" 80 84 Red Diary 'Hidden Track''' |- ! scope="row"| "Picnic" () | rowspan="7"| 2019 | 31 || 39 | rowspan="2"| Puberty Book I Bom|- ! scope="row"| "Seattle Alone" | 43 || 49 |- ! scope="row"| "25" | 33 || rowspan="16" | rowspan="5"| Two Five|- ! scope="row"| "XX" | 30 |- ! scope="row"| "Taste" | 50 |- ! scope="row"| "Day Off" () | 59 |- ! scope="row"| "XX" | 117 |- ! scope="row"| "Blank" () | rowspan="4"| 2020 | 108 | rowspan="3"| Puberty Book II Pum|- ! scope="row"| "Dandelion" () | 143 |- ! scope="row"| "Counseling" () | 164 |- ! scope="row"| "Red Lipstick" () | 31 | Filmlet|- ! scope="row"| "Love Story" | rowspan="3"| 2022 | 16 | rowspan="3"| Seoul|- ! scope="row"| "What Makes Us Beautiful" () | 187 |- ! scope="row"| "Star" () | 186 |- ! scope="row"| "Rome" | rowspan="4"| 2023 | 158 | rowspan="3"| Love.zip|- ! scope="row"| "When Love Becomes Goodbye" () | 77 |- ! scope="row"| "Good Night" () | 180 |- ! scope="row"| "Eternal Love" () | 33 | Merry Go Round''
Concert and tours Headlining concerts and tours BOL4 1st Solo Concert "Red Planet" (2016) BOL4 1st Concert in Taipei (2017) BOL4 2nd Solo Concert "Imagine" (2017-2018) BOL4 3rd Solo Concert "Travel" (2018) 2019 BOL4 Spring Solo Concert "Flower Energy" (2019) 2019 BOL4 Asia Tour "Blossom" (2019) 2019 BOL4 Tour Concert "Two Five" (2019) BOL4 Japan Live Tour 2020 "Love" (2020) BOL4 Concert "Seoul" (2022) 2023 BOL4 Concert in Taipei (2023) BOL4 Concert "Love.zip" (2023) 2023 BOL4 Asia Tour "Love.zip" (2023) 2024 BOL4 Concert "Bloom" (2024) 2025 BOL4 Asia Tour "Bloom" (2025)
BOL4 1st Solo Concert "Red Planet" (2016) Concert Date City Country Venue Red Planet No. B41120 November 20, 2016 Seoul South Korea Baekam Art Hall Red Planet No. B4120304 December 3, 2016 Ewha Womans University (Samsung Hall) December 4, 2016
BOL4 1st Concert in Taipei (2017) Date City Country Venue Attendance September 9, 2017 Taipei Taiwan Legacy Taipei 2,300
BOL4 2nd Solo Concert "Imagine" (2017-2018) Date City Country Venue Attendance December 16, 2017 Seoul South Korea Blue Square iMarket Hall 6,500 December 17, 2017 December 31, 2017 Busan Sohyang Theatre Shinhan Card Hall February 3, 2018 Hong Kong KITEC (Rotunda 3) 1,500Total 8,000
BOL4 3rd Solo Concert "Travel" (2018) Date City Country Venue Attendance 2018 BOL4 2nd Concert in Taipei "Travel Together" June 30, 2018 Taipei Taiwan Taipei International Convention Center 3,000 2018 BOL4 3rd Solo Concert "Travel" July 14, 2018 Seoul South Korea Olympic Hall 6,000 July 15, 2018 2018 BOL4 1st Concert in Japan -旅- August 8, 2018 Tokyo Japan Toyosu PIT 2,500Total 11,500
2019 BOL4 Asia Tour "Blossom" Date City Country Venue 2019 BOL4 Spring Solo Concert "Flower Energy" May 4, 2019 Seoul South Korea Blue Square iMarket Hall May 5, 2019 2019 BOL4 Japan Premium Showcase June 6, 2019 Osaka Japan Banana Hall June 8, 2019 Tokyo TSUTAYA O-East 2019 BOL4 Asia Tour "Blossom" June 15, 2019 Hong Kong KITEC (Star Hall) July 13, 2019 Bangkok Thailand Moonstar Studio 8 November 9, 2019 Taipei Taiwan National Taiwan University Sports Center 1
2019 BOL4 Tour Concert "Two Five" Date City Country Venue November 30, 2019 Busan South Korea Sohyang Theatre Shinhan Card Hall December 1, 2019 December 7, 2019 Daegu EXCO (Auditorium) December 8, 2019 December 14, 2019 Daejeon Woosong University (Art Hall) December 15, 2019 December 21, 2019 Gwangju Chosun University (Sunup Hall Auditorium) December 22, 2019 December 28, 2019 Seoul Ewha Womans University (Grand Hall) December 29, 2019
BOL4 Live Tour 2020 "Love" Date City Country Venue January 16, 2020 Osaka Japan Zepp Namba January 18, 2020 Tokyo Toyosu PIT
BOL4 Concert "Seoul" (2022)