A 13-episode anime adaptation produced by Kyoto Animation aired in Japan between April and June 2009. An additional original video animation (OVA) episode was released in January 2010. A 26-episode second season, titled K-On!! (with two exclamation marks), aired in Japan between April and September 2010, with an OVA episode released in March 2011. An animated film based on the series was released in Japan on December 3, 2011. Bandai Entertainment had licensed the first season until their closure in 2012. Sentai Filmworks has since re-licensed the first season, in addition to acquiring the rights to the second season and film. The title of the series comes from the Japanese word keiongaku, which means popular music. K-On! has achieved strong sales in Japan, and by 2011 gross revenues had reached over ¥15 billion.
A 13-episode anime adaptation directed by Naoko Yamada, written by Reiko Yoshida, and produced by Kyoto Animation aired between April 3 and June 26, 2009 on TBS in Japan. The episodes began airing on subsequent networks at later dates which include BS-TBS, MBS, and CBC. The TBS airings are in 4:3 ratio, and the series began airing in widescreen on BS-TBS on April 25, 2009. Seven BD/DVD compilation volumes were released by Pony Canyon between July 29, 2009 and January 20, 2010. An additional original video animation (OVA) episode was released with the final BD/DVD volumes on January 20, 2010. The BD/DVD volumes contained extra short anime titled Ura-On!.
The series later began airing on Japan’s Disney Channel from April 2011. Animax has aired the anime in Hong Kong, Thailand, and Taiwan. Both an English-subtitled and English-dubbed version by Red Angel Media began airing on March 16, 2010 on Animax Asia. At their industry panel at Anime Expo 2010, anime distributor Bandai Entertainment announced that they have acquired K-On! for a DVD and Blu-ray Disc release, with Bang Zoom! Entertainment producing an English dub for the show. The series was released over four volumes in standard and limited editions for each format starting on April 26, 2011. Bandai released the full first season on DVD under their “Anime Legends” line on February 7, 2012. Manga Entertainment released the series in the UK in individual DVD volumes during 2011, and in a complete DVD of the first season on April 30, 2012. A planned BD box set release in 2012 was cancelled. Sentai Filmworks has licensed the first season and re-released the series on DVD on September 23, 2014. Sentai also re-released the series on Blu-ray on September 1, 2015.
It was displayed on screen at the Let’s Go live concert in Yokohama, Japan on December 30, 2009 that a second season would be produced. The second season, titled K-On!! (with two exclamation marks), aired with 26 episodes on TBS in Japan between April 7 and September 28, 2010. An additional OVA episode was released with the final BD/DVD volumes on March 16, 2011. As with the first season, the BD/DVD volumes contained extra short anime titled Ura-On!!. This season has also aired on Animax Asia starting October 20, 2010. Sentai Filmworks licensed the second season and released the series on DVD and Blu-ray in two boxsets released on June 19, 2012 and August 28, 2012 respectively. The series continues using the English dub cast from the previous season.
- Yui Hirasawa
- is the lead guitarist and split vocalist of the Light Music Club who plays a Heritage Cherry Sunburst Gibson Les Paul Standard electric guitar (before she knew how to play the electric guitar, the only instrument she knew how to play was the castanets) that she nicknames “Gīta”. She does not get good grades in school (though when properly coached, she can achieve astounding results) and is easily distracted by trivialities (mainly those deemed cute and adorable). Yui is clumsy and easily spaces out most of the time; as a result, she can be forgetful and is sometimes oblivious to the situation around her. Yui has shoulder-length, brown hair (a little longer than Ritsu’s) which she accessorizes with two yellow hair clips, and brown eyes. She takes a huge liking for any kind of food (though she never gains weight, which is greatly envied by Mugi, Mio, and Sawako). She has a younger sister named Ui, who is very mature and acts as the “older sister” of Yui, taking care of her and keeping her in line. Yui works extremely hard to get better at playing guitar. During performances, Yui plays with amazing energy and joy which usually results in great response from the audience.
- As a musician, Yui has absolute pitch—she can tune her guitar perfectly without a tuner, which greatly impresses Azusa, who has played the guitar much longer than Yui. She has a very easy-going nature, but has incredible focus and retention when she has a clear goal in sight; unfortunately, this is limited to only one subject at a time, and her other skills deteriorate quickly (for example, Yui is at one point pressed to make up failing test scores, and she quickly brings her math skills up to par at the expense of her guitar knowledge). Despite all of this, Yui is still devoted to her band and will always practice hard enough for the club. At school, she has become quite admired for her great voice. However, she is known to forget her lyrics mid-performance as well as overdoing things, making her unable to perform sometimes. Mio was the lead vocalist at first, since Yui could not play the guitar and sing at the same time. Yui is also known to write childish lyrics as Ui has assisted her in creating them.
- Mio Akiyama
- is the bassist, songwriter, and split vocalist for the light music club. She is a shy girl who is in the light music club. She plays a left-handed, 3-Color Sunburst Fender Jazz Bass with a tortoiseshell pickguard, though is shown playing a Fender Precision Bass in the first manga volume. She uses D’Addario EXL160M medium bass strings. Her bass is given the name Elizabeth later in the anime. While she originally intended to join the literary club, she was forced into the light music club by her childhood friend and the club’s president/drummer, Ritsu. She gets excellent grades in school and is often mature and strict especially where Ritsu is involved; her weakness is the horrific; she is often incapacitated with fear when stories involving ghosts, blood, injuries, haunted houses, barnacles or other disturbing topics come up. She also has a fear of being in the spotlight and gets embarrassed easily, and is often subject to teasing from Ritsu and Sawako, their club adviser and eventual third-year homeroom teacher. Mio has long, straight black hair and gray eyes (that are angled slightly more than the other characters). She cites that she chose bass since it is not the center of attention in the band, unlike the guitarist. Mio is more technical when it comes to music, and Yui often comes to her when she is in need of more guitar tutorials.
- Mio is the split vocalist of the band, though given her dislike of being center stage, she tries to avoid taking the lead vocal if possible, generally singing if Yui is unable to. She writes most of the songs, although they usually feature some odd and overly girlish lyrics like “Light and Fluffy Time”. As she is left-handed, she becomes entranced whenever she sees left-handed instruments because of their rarity. After their first live performance, the attractive Mio gained a huge fan following (in no small part due to an unfortunate accident that occurred at the end of the show), led by an infatuated former student council president. Also resulting from her sudden popularity, most of her classmates voted that she portray Romeo in their class play. Mio comes to greatly enjoy her time at university as she encounters many new experiences. She is also able to overcome some of her shyness and make new friends such as Sachi and Ayame.
- Ritsu Tainaka
- is the self-proclaimed president of the light music club and the leader of Hokago Tea Time who plays a yellow Rick Marotta Signature Yamaha Hipgig drum kit (with an add-on floor tom in the opening credits only) combined with a cymbal set from Avedis Zildjian, though is shown playing a white Yamaha Absolute Series drumkit in the anime’s closing credits. She has an ambiguous yet upbeat personality, much like Yui, but often has trouble remembering important club activities and announcements and gets constantly rebuked by Mio and Nodoka for forgetting to send in important forms concerning the club. Ritsu is cheerful, often likes making jokes and is sarcastic most of the time. She is skilled at brainstorming ideas that earn money for the club. Ritsu has shoulder-length, brown hair, with her bangs pulled back with a yellow hairband, and gold-colored eyes. She wears her school jacket open. She says she chose to play the drums because they are “cool”, but later admits that she has trouble playing instruments which involve intricate finger movements such as the bass, guitar and keyboard.
- She is Mio’s childhood friend and will often take the opportunity to tease her whenever Mio is cowering from something. She is also known to become easily jealous of Mio’s other high school friends, even going as far as spying on Mio when on outings with them. Ritsu is always on the go and will stop at nothing for the success of the light music club. Despite her rough mannerisms and speech, she gets cast as Juliet by the majority of her classmates in their class play rendition of Romeo and Juliet and, in the end, manages to act like a proper girl. In the anime, she states her favorite drummer is Keith Moon of The Who. She is skilled at cooking. She has a younger brother named Satoshi.
- Tsumugi Kotobuki
- Tsumugi, often referred to as Mugi by her friends, is a wealthy Kansai girl with a gentle and sweet personality who plays a Korg Triton Extreme 76-key keyboard, though she is also seen playing a Korg RK-100 keytar in the closing credits of the first season, and a Hammond organ in the closing credits of the second season. She originally intended to join the choir club, but joins the light music club instead after receiving an invitation and encouragement from both Mio and Ritsu. Tsumugi is considered a piano prodigy since she has been playing the piano since she was four and has experience in winning various piano contests. Tsumugi has written several songs for the light music club, as well as singing the back vocals in several other songs. She is a good student and has long, pale blonde hair, blue eyes, unusually large eyebrows that apparently run in her family, and a fair complexion that the other characters do not have, but she does not get sunburned. She however, has great difficulty playing electric guitar.
- She is the daughter of a company president, and her family has several villas in various places around Japan (and even one in Finland). Since her father also owns a maid café, she often brings confectionery and an assortment of sweets and pastries to the club room, and she diligently makes tea with a tea set which is kept in their club room. Despite her wealth, she is fascinated by and finds joy in “normal” activities, such as ordering fast food, sharing french fries with her club mates, holding down part-time jobs and haggling over prices. Tsumugi displays a rebellious streak occasionally, diverting from her normally well-behaved and mature demeanor to the surprise of the others. She also displays a childlike eagerness from time to time, and possesses unusually high strength, being able to effortlessly carry around her own keyboard, Ritsu’s drums, amplifiers, and at one point beating an arm-wrestling game in an arcade.
- Tsumugi is often entranced by the sight of two girls interacting closely together, sometimes imagining something more risqué in her head. While a lot of things do not bother her, she is fairly conscious about her weight (just like Mio), and she gets a bit anxious when her family’s staff start spoiling her friends during villa visits. She later begins learning how to play the guitar from Azusa. Tsumugi has a childhood friend several years younger than her named Sumire Saitō, who is a daughter of the family that serves the Kotobuki household. Tsumugi grew up home schooled, and therefore spent very little time in the outside world. Because of their close friendship, Sumire would purchase everyday items for Tsumugi, like manga that she was not normally allowed to see. Tsumugi was rather taken by some of the yuri manga she received, which may have influenced her later perceptions about relationships. When Sumire started high school, Tsumugi wanted her to experience the light music club on her own, but due to Sumire’s shyness Tsumugi came up with the excuse of sending her to the club room to pick up the tea sets that had been left there and told Sawako when Sumire did join that it was okay to leave the tea sets there.
- Azusa Nakano
- is a student in the same year and class as Yui’s sister Ui, who joins the light music club and becomes the rhythm guitarist, playing a Fender Mustang electric guitar. She eventually names her guitar Muttan, as it is a Mustang. She is a self-proclaimed “novice” guitarist who has been playing the guitar since she was in the fourth grade, and her parents are working in a jazz band. She is more serious than the other girls, and does not like to admit how she really feels. She often finds herself bewildered by the tea parties and cosplaying aspects of the club, when she would rather just practice, and is curious about how the club is able to play so well despite their problems and lack of practice. However, she has a certain weakness for cakes and can be calmed down rather easily, sometimes by just being petted. She is constantly a victim of Yui’s physical affection and is nicknamed Azu-nyan after trying on a pair of cat ears and meowing (“nyan” being the equivalent of “meow” in the Japanese vocabulary). Despite this, Azusa is not too good with cats. Azusa has long black hair, which she wears in pigtails, and brown eyes. While Azusa is talented in guitar, she has trouble singing while playing unlike Yui and Mio.
- In the band, she looks up to Mio the most due to her maturity and the fact that she is an experienced bassist, even trying to give Mio chocolate on Valentine’s Day. However, she sometimes unintentionally makes remarks concerning Mio’s weaknesses, such as her weight. She also finds Mugi very beautiful, and envies her hair and large eyes, and later starts teaching her how to play guitar when the two are alone in the club room. Since joining, Yui comes to her for advice on playing guitar, as well as maintenance. She gets a tan extremely easily, once during their time at the beach and another during a music festival (even after applying sunscreen). As a result, she frequently gets sunburned as well. She gets lonely very easily, and often worries that everyone in the club will leave her, as they are one year older and eventually will graduate. Due to this, the rest of the girls buy her a turtle to look after, naming it Ton.
- Outside of the band, she often hangs out with Ui and Jun whenever the other girls are busy. When the others graduate, she becomes the new light music club president alongside Ui and Jun, who decide to join her. Together with two new members, Sumire and Nao, they form a new band called “Wakaba Girls”. During the Wakaba Girls’ first summer training camp Azusa reveals to Sawako her belief that she is unable to act like a proper president for the light music club; however, Sawako suggests that there is no proper way to define what it means to be a president and that Azusa will do just fine. While on that same training camp Azusa is convinced by the others to become the band’s vocalist despite her prior reservations on the issue.