Which games use the Konami code?

[Petzbreeder]

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Does anyone know which games use the Konami code and what the code does in those games?
I hear people talking about it from time to time, but I've never been able to unlock anything in any games that I own.

Do Nintendo games use it?

[Captain Jigglypuff]

NES Konami games do. Contra is the most famous one to do so. Not sure about other games.

[Del]

Here are all the Konami games that use the code and here are all the other games or apps or websites that use the code. As you can see it's a pretty popular code, definitely the most well known cheat code in video game history at least.