When playing some of your games, you might find cheaters.

In the context of the rules on Lichess, the general agreement is that cheaters use means other than their own chess intellect to win rated games or boost their ratings. Examples of cheating include:

• Using a computer player (or chess engine) to play the game
• Lending access to a game to another individual for help with moves
• Creating additional Lichess accounts to boost one rating

The cheater's profile may include a header saying, "This player uses chess computer assistance," if the cheater has been caught cheating that way already. This flag will be visible in public to everybody except the cheater. Once caught, their ratings are reset to 1200.

There are many ways through which both the system and its staff detect cheaters, but that doesn't mean they will all be noticed instantly. After finishing rated games, you can see a "view game statistics" link to see time statistics to help you think as to whether your opponent cheated. It is acceptable to cheat in casual games if you make sure your opponent knows you are not playing normally, but please don't cheat against cheaters for points. The best thing is to protect everybody else.

If you think your opponent might have cheated, you could publicly post on the forum, but it is probably safer to message a staff member if you are not absolutely certain. The general public might have some experience playing the person, but this history as well as much more information is reviewed by the Lichess staff.

• legend (long-term cheaters experience)
• mb (Miss you! Good luck with work.)
• Mephostophilis (short-term cheaters experience)
• thibault (site engineer)