The music of Nier was composed by Keiichi Okabe with members of his studio, Monaca, Kakeru Ishihama and Keigo Hoashi, and Takafumi Nishimura of Cavia.

Returning collaborators include Keiichi Okabe and the Monaca team on composing duties and Emi Evans on vocals, along with several other singers and lyricists.

Nier: Automata Original Soundtrack was highly reviewed by critics, and the album peaked at number 2 on the Oricon charts.

The soundtrack to Nier was composed by a collaboration of the studio Monaca, consisting of Keiichi Okabe, Kakeru Ishihama, and Keigo Hoashi, along with Takafumi Nishimura from Cavia, the game's developer.

Some tracks were used in ways that the composers did not envision, such as "Grandma", which was expected to be used in the prologue of the game but was instead chosen as a boss battle theme.

Okabe was allowed a great deal of freedom regarding what the music was to sound like; game director Taro Yoko's main request was that he use a lot of vocal works.

She is the singer for the band freesscape, and had previously worked on video game projects such as the Etrian Odyssey arrange albums.

The composers gave her preliminary version of songs and the style they wished the language to be in, such as Scottish Gaelic or French, and she invented the words.

He also did not want easily recognizable lyrics to be sung in the background while the characters were speaking, and for any noticeable words to instead evoke emotions in the player.

A change from the previous score was a shift to portraying a more mechanical and brutal theme and environment than Nier, which had focused on grasslands and villages.

Nicole and Nami Nakagawa joined with Evans to form a three-part chorus for some of the musical work, including a boss theme featured in the game.

Instead, Shindo designed a realistic soundscape using a system to manage echoes in real time, determining how much reverberation to generate based on current surroundings.

[10] The soundtrack to Nier is largely composed of melancholy acoustic pieces which heavily feature vocals by Emi Evans.

Of the 43 tracks included in the released soundtrack album, only 9 do not have any vocal component to them; these are the four versions each of "Dispossession" and "Yonah", as well as "Dance of the Evanescent".

[2] For "Ashes of Dreams", Evans convinced the composers that one song in the soundtrack should have recognizable lyrics rather than futuristic English as they originally planned.

"The Wretched Automatons" is sung in a variant of English and was recorded prior to the addition of the mechanical sounds that run throughout the track, while "Kainé" is in a version of Gaelic.

by Yuji Sekiguchi were included in the Square Enix Official Best Collection guitar solo sheet music book, published by KMP in May 2011.

[11] Don Kotowski of Square Enix Music Online praised the "captivating vocal work" and "exquisite" composition.

[12][13] Jayson Napolitano of Original Sound Version also praised the album, saying that it was "hands down one of the best soundtracks Square Enix has published over the years".

The resulting eclectic mix of styles is primarily electronic, but also includes a multiple-piano arrangement of "Grandma" and a klezmer rendition of "Shadowlord's Castle".

The tracks were arranged and played by several different artists, namely Keigo Hoashi, Kumi Tanioka, Masato Kouda, Ryuichi Takada, and Yuri Misumi.

[31] The first EP was positively reviewed by Brad Hayes-Raugh of RPGFan, who "greatly enjoyed the direction this album takes", though he did note that some of the pieces did not quite meet his high expectations.

He concluded that "the tracks give a fresh spin on some great pieces of video game music and keep the spirit of Nier alive and well.

[32] The team wanted to give a "sense of renewal" with the pieces, and made sure not to change the "tone" of the songs, but added live instruments and choral elements.

For example, in "Kainé / Salvation", more live instrumentation gave what they felt was a "richer sound", and where the original looped to start over the updated version instead repeats with slight changes and additions.

Its music was again composed by Keiichi Okabe and the Monaca team, with Emi Evans, J'Nique Nicole, and Nami Nakagawa on vocals, Takanori Goto on guitar, and additional contributions by several artists.

[37] NieR: Automata Original Soundtrack peaked at number 2 on the Oricon charts,[38] with over 28,000 copies sold in its first week in Japan.

[42] On December 20, 2017, an album of arranged music and unreleased tracks of NieR: Automata was released by Square Enix in two discs.

It contains five tracks each from Gestalt & Replicant and Automata, arranged by Sachiko Miyano and Kosuke Yamashita and featuring solo vocal performances from Emi Evans and J’Nique Nicole.

[54] On July 15, 2015, an officially licensed arrangement of "Song of the Ancients" from Nier, along with a music video, were released by OverClocked Records.