Why is card counting considered illegal?

Card counting is NOT illegal under federal, state and local laws in the United States as long as players don’t use any external card-counting device or people who assist them in counting cards. In their effort to identify card counters, casinos can ban players believed to be counters — sort of.

Why is counting cards considered cheating?

Card counting is NOT cheating. Card counting is simply using your brain, like a winning chess player. Fortunately, using your brain is still perfectly legal in the US!