Konami code

From NEC Retro

The Konami code or Konami command (コナミコマンド) is a cheat code which regularly appears in video games. Originally left in by accident by Konami developer Kazuhisa Hashimoto in the Famicom port of the 1985 arcade shooter, Gradius, it rose to fame with its inclusion in the NES version of Contra (where it was often dubbed the "Contra code" or "30 lives code", almost necessary for players to have a chance of beating the game). It has subsequently been used in a wide variety of products, both those published by Konami, and others, becoming perhaps the most recognised cheat code in video gaming.


In its original form, the Konami code is:


This code was chosen due to being relatively easy for game testers to remember, but difficult to input accidentally. In Famicom Gradius the code is to be entered while the game is paused, and if successful, will upgrade the weapons of the Vic Viper ship, making the stage easier to complete. The  START  is technically optional; the state of Gradius changes after A but  START  is required to unpause the game and see the effects. As a result, not all games include it in their implementations.

Many minor variants exist such as exchanging B and A for 2 and 1 or and for consoles which lack those buttons, or swapping and for shoulder buttons. Nintendo consoles such as the Famicom have the A and B buttons reversed, so some implementations re-reverse these buttons, emulating the layout of the code, but not the button names themselves.

It is not unusal to see further deviations from the code, such as inverting the directions or requiring more button presses, though at this point one could argue they are no longer Konami code variants.

Use in NEC games

While there are some exceptions, for many years, the Konami code was restricted to just Konami games, becoming more mainstream after the dawn of the internet and knowledge of such a code became more widespread. As such, comparatively few games for NEC consoles implement the code.


Sega Retro has more information related to Konami code