Visual kei (ヴィジュアル系 bijuaru kei?, lit. "visual style" or "visual system") is a movement among Japanese musicians, that is characterized by the use of varying levels of make-up, elaborate hair styles and flamboyant costumes, often, but not always, coupled with androgynous aesthetics. Some sources think that visual kei refers to a music genre, with its sound usually related to glam rockpunk rock and heavy metalHowever, this is contradictory to the fact that visual kei acts play various genres, including those unrelated to rock such as electronicpop, etc. Other sources, including members of the movement themselves, state that it is not a music genre and that the fashion and participation in the related subculture is what exemplifies the use of the term.

While visual kei is not bound to a specific music genre, the whole movement is generally associated with several styles of music, including, but not limited to, rock, pop, electronic music, neoclassical, industrial and heavy metal. More often, bands draw influence from a number of disparate musical sub-genres in order to create a distinct sound. Many bands revolve around a concept that guides their musical and visual approaches, a notable example being the vampire story themed band Versailles, with a neoclassical metal sound in line with their rococo-inspired visual style. It is rather common for long-running visual kei bands such as X Japan and Dir en grey to undergo numerous stylistic changes in terms of their sound, with the former example venturing into progressive metal and the latter eventually leaning into metal-core.

The archetypal visual kei sound, however, is more or less rooted in hard rock and heavy metal, featuring loud, distorted guitars, vigorous vocals, emphatic drumming, and melodic hooks. Guitarists would often employ melodic power riffs and palm muting, and solos are fairly common. Guitarists may play in standard tuning or in Drop D, with oshare-kei and tanbi-kei artists keeping a standard sound or tuning higher for guitar solos, and less mainstream acts tuning lower than Drop D or Drop C. Extreme metal acts, particularly Nagoya and Angura acts, will go as far as tuning to Drop B or A, or even eschewing traditional six-string guitars for seven or eight-string guitars, resulting in a thick, hollow and heavy tone similar to djent/mathcore acts.

Visual kei singers often have moderate to high vocal ranges, with vocal lines sung clearly. A few bands, especially those in the oshare-kei and nu metal sub-genres, employ distorted or auto-tuned vocals. Screamed vocals are very common in the genre and can range from faint, breathy vocals to inhuman shrieking. Frequently emulated vocalists in visual kei include Kiyoharu (ex-Kuroyume), Gackt, and Kyo (Dir en grey)

It is fairly common for drummers to employ fast rhythms using double bass pedals or, as with many bands, two bass drums. Metal-influenced bands such as X JAPAN play pounding beats and rapid bass drumming similar to thrash or power metal bands. Even more uncommon, but not unheard of, are blast beats. Visual kei drummers often employ complex fills and shuffled beats to add variety and, in live performances, signal mosh pits.

As with any popular style of rock or metal music, it is common for the bass guitar to be faint. Bassists in visual kei, unlike bassists in other musical styles, are as important and noteworthy as the lead or rhythm guitarists. They would often play savage riffs with great speed and technicality, usually timed with the rhythmic patterns of the kick drum or the rhythm guitar. Some bassists employ fingerstyle techniques or in some cases, slapping.