Is counting cards in blackjack illegal?
Card counting is only illegal if you are using a device to do so. If you are doing it in your head, it is not illegal. Casinos have about .05% advanage in black jack. Card counters can sway this advantage to about 1% in favor of the player. Casinos can refuse service to anyone, so if you are suspected of card counting, you will be asked to leave. Sometimes forcefully. Hope this answers your questions.
