Tesseract play a specific style of progressive metal that often features polyrhythmic riffs, odd time signatures, and several atmospheric layers. The band have stated that they do not compose their music with specific polyrhythms in mind, but play what they feel fits the groove. They also include a mid-range distorted guitar tone and melodic clean passages, heavily influenced by ambient music. The band typically plays in the style of the subgenre djent, pioneered by Meshuggah and SikTh. The vocal style of the band has seen a considerable shift. On One, Daniel Tompkins employed a mixture of clean and harsh vocals, with an emphasis on long, drawn out notes. However, Ashe O'Hara's performances on Altered State dropped the harsh vocals entirely, in favour of a more melodic style with an emphasis on strong melodic "hooks". In an interview with Metalspree, Ashe stated, "Right now, being ourselves is to have purely melodic vocals. With ‘One’ they felt they had to have harsh vocals in order to be accepted by the community. But, they’ve never really wanted to be that type of band".