

While its predecessor used five keys, the IIDX controller had seven. It was designed to simulate the experience of a DJ performing songs live at a music venue which gave it a "club Visual Jockey feel." The game was released on February 26, 1999. : 54–58 : 297 Bemani conceived Beatmania IIDX as a sequel to Beatmania. The studio made more music-themed video games following its release, including Pop'n Music and Dance Dance Revolution. Its surprise success prompted the developer to rename itself Bemani, a portmanteau of the game's title.

In 1997, Konami distributed its Games & Music Division's (G.M.D.) Beatmania in Japan as an arcade DJ simulator, significantly influencing rhythm games. Clearing four or more stages in Internet Ranking results in a password, which can be submitted to Konami so that the player's score is registered and shown in worldwide rankings. The 7 Keys mode utilizes all buttons and Expert has the player select a course and obtain the highest score. 5 Keys is a mode where the player uses "3 white keys on bottom and 2 black keys on top" like in Beatmania. The controls in the 4 Keys mode are limited to only the white buttons. IIDX has four play modes: 4 Keys, 5 Keys, 7 Keys, and Expert. Failing to do so depletes the gauge and can prematurely end the song. Hitting notes with accurate timing increases the player's score and groove gauge bar, allowing the player to finish the stage.

The objective of Beatmania IIDX is to perform songs using a controller with seven key buttons and a scratchable turntable. The player hits notes during the M-Flo song "The Theme from Flo Jack".
