During the title screen before the game demo begins, the player could press the following sequence of buttons on the game controller to enable the cheat:
The code has also found a place in popular culture as a reference to the third generation of video game consoles, such as in the film Wreck-It Ralph.  It appears in the Amazing World of Gumball episode called "The Tape" when Gumball attempts to cheat in real life. The code is also present as an Easter egg on a number of websites.
The code was first used in the 1986 release of Gradius for the Family Computer/Nintendo Entertainment System but was popularized among North American players in the NES version of Contra, for which it was also dubbed both the "Contra Code" and "30 Lives Code".
The Konami Code was created by Kazuhisa Hashimoto, who was developing the home port of the 1985 arcade game Gradius, a scrolling shooter released on the Famicom and NES in 1986. Finding the game too difficult to play through during testing, he created a cheat code to give the player a full set of power-ups (normally attained gradually throughout the game). The code was still present in the released Gradius after Hashimoto forgot to remove it. Players discovered and shared the code.
The Konami Code was thus included in the series' other sequels and spin-offs, with some key differences:
- In the Super Famicom/SNES version of Gradius III, the original code destroys the player's ship. However, replacing ← and → with the L and R triggers of the SNES controller powers up the ship.
- In the most recent iteration of the series—Gradius Rebirth on the Wii—the Wii Remote's 1 and 2 buttons fill in for A and B, respectively.
- In DSI Sound, using the Konami Code while one is listening to their own music on the SD Card, a cyclist appears and wins the race.
The code has been subsequently re-used in a large number of other games.
The original version of the cheat code was designed for the NES controller. The exact sequence varies from game to game and has been adapted to fit the button layouts of different video game consoles, mostly the A and B buttons. For example:
- Any code for a PlayStation controller, which uses shapes instead of letters, would use ", ", appearing even in Konami's Dance Dance Revolution series, input on the dance pad.
- In mobile phone games by Konami, they are substituted with 5 7 3 on the numerical pad, which is the goroawase pronunciation for "konami."
These deviations may occur:
- for purely operational reasons (e.g., if the code must be entered while the game is paused, the code might be altered to avoid hitting the unpause button),
- to keep powerful upgrades better concealed while still referencing Konami, or
- through an error in writing the code in the game.
Despite the differences, though, these codes are still often referred to in general discussion as "Konami Code", "Conami Kode", or, less commonly, "Pseudo-Konami Code".
A common misconception is that the code ends with Start or Select Start. In Contra, the player must press Start after entering the code in order to start the game, or press Select Start to switch to two-player mode and then start the game, leading to the confusion. In other games, pressing these buttons will cause the code to not work.
- The editors of GamePro and GamerHelp.com, "The 'Contra Code:' We Must Never Forget," GamePro 235 (April 2008): 63.
- "Cracking the Code: The Konami Code". 1up.com. Retrieved 2008-03-15.[dead link]
- Konami Code at TV Tropes
- Robinson, Tasha (November 1, 2012). "Wreck-It Ralph". A.V. Club. Retrieved November 19, 2012.
- Carvin, Andy (June 14, 2010). "Geek Trick Of The Week: Newsweek Vs. The Zombies.". NPR. Retrieved June 14, 2010.
- "The Konami Code Makes ESPN.com Magical!". Kotaku.
- "Konami Code triggers Easter egg on Facebook too". CNET. 2009-05-08.
- Moore, Matthew (September 17, 2009). "Google easter eggs: 15 best hidden jokes". The Daily Telegraph (London).
- "Geek Trivia: The cheat goes on". techrepublic.com. Retrieved 2008-04-16.
- Schaumberg, Bill. "6 Games That Put Insane Detail Into Stuff You Didn't Notice". Cracked.com. Retrieved 2013-11-01.