How to Use Retro Cheat Codes: Game Genie, GameShark and Action Replay Explained

By · October 21, 2026 · 7 min read

Every cheat code page on this site lists codes for a specific device: Game Genie, GameShark, Action Replay and a few others. If you've never used one, the long strings of letters and numbers can look like nonsense. This guide explains what each device was, how to tell their codes apart, and how to actually get them working today, whether you're playing on an old console or in an emulator.

Two kinds of cheats

Built-in cheats were put in the game by its developers. The Konami code, button combinations on the title screen, and passwords that unlock a level select all fall into this group. You don't need anything extra to use them.

Cheat device codes are different. A cheat device sits between the console and the game and changes values in the game's memory as it runs: the number of lives, the timer, how much money you have. The codes are instructions that say which value to change and what to change it to. That's why they work on almost any game, and why they look like gibberish.

The devices, and what their codes look like

Game Genie. The first big cheat device, made by Codemasters and sold by Galoob for the NES, then for the Super NES, Genesis, Game Boy and Game Gear. NES codes are six or eight letters long, like a word that isn't one. Super NES and Genesis codes look like XXXX-XXXX, and Game Boy codes are in groups of three. Codes for one system never work on another.

Pro Action Replay and Action Replay. Datel's devices, popular in Europe. Codes are eight hexadecimal characters (the numbers 0 to 9 and the letters A to F). Datel also made the later Action Replay DS, whose codes are long blocks of hexadecimal split over several lines.

GameShark. The best-known name in North America, covering the Nintendo 64, PlayStation, Game Boy, Game Boy Color and Game Boy Advance. Outside North America the same device was usually sold as an Action Replay. A typical N64 or PlayStation code is eight characters, a space and four more, like 8033B21E 0008, and many cheats need two or more lines entered together.

Code Breaker and Xploder. Rival devices with their own code formats, mostly for the PlayStation and Game Boy Advance. Their codes only work on the matching device or in an emulator that supports that format.

Emulator memory codes. Some lists use a plain address:value format. These were written for emulators and never ran on a physical device.

Master codes

Many GameShark and Action Replay lists for the N64, PlayStation and Game Boy Advance start with a code called the master code, enable code or "must be on" code. It gives the device a way into the game. If a list has one, switch it on together with whatever cheat you want, or the other codes may do nothing at all. Our cheat pages point out when a list includes a master code.

Using codes on original hardware

If you have the real device, it plugs in between the game and the console. The Game Genie and the N64 GameShark sit on top of the cartridge slot, with the game plugged into them. Early PlayStation models had a port on the back for cheat devices, and later versions came on a disc. In every case you turn the console on, type the codes on the device's own menu, then start the game.

Using codes in an emulator

Most emulators have a cheat menu that accepts these codes, so you don't need any extra hardware. In RetroArch, it works like this:

  1. Start the game, then open the Quick Menu and choose Cheats.
  2. Either load a ready-made cheat file for your game (RetroArch can download its cheat collection through the Online Updater), or choose to add a new code.
  3. For a new code, enter a description, type or paste the code, and set it to enabled. For multi-line codes, put a plus sign between the lines if the field only takes one line.
  4. Choose Apply Changes and go back to the game.

Most RetroArch cores accept the original Game Genie, Action Replay and GameShark formats as they are. Standalone emulators work much the same way: look for a Cheats menu, add the code, enable it.

When a code doesn't work

  • Check the version. Codes often only work on one region or revision of a game. A code for the American release can do nothing on the European one. If a list doesn't work, try a list for another version.
  • Turn on the master code if the list has one.
  • Enter every line. A cheat with three lines needs all three, exactly as written.
  • Match the format. A Game Genie code won't work if your emulator expects it as an Action Replay code. Some emulators ask which format you're entering.
  • Try a different moment. Some codes only take effect after the level loads or after you load a save.

Protect your saves

Cheats change the game's memory directly, and once in a while that confuses it. Codes that give you every item or change your stats can occasionally corrupt a save. Back up your save before you experiment, switch cheats off before saving if you can, and don't leave codes running that you aren't using.

Where to start

A few of the most popular lists on the site: Super Mario Bros. cheats, Super Mario 64 GameShark codes, Pokemon Red codes and Sonic the Hedgehog cheats. Or search for any game on the cheat codes page.

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