Blue catfish are the largest American catfish. They can grow to over 55 inches long and can weigh over than 100 pounds. Blue catfish can live up to 20-25 years.

Adult blue catfish have stout bodies with prominently humped back in front of the dorsal fin. They have deeply forked tails similar to channel catfish, but lack spots and have a large straight edged anal fin. The back and upper sides are blue to slate gray, and the lower sides and belly are white.