King crabs live all over the world, including places such as Alaska, Korea, Russia, New Zealand and Africa. They are generally large and have been known to reach more than 20 pounds in weight. Upon first glance, male and female king crabs look nearly identical. Female crabs tend to be smaller, but you cannot go strictly by size if you want to tell the sex of a king crab. There is one distinct feature that king crabs have that give their gender away.
Put on a pair of thick rubber gloves to protect your hands and fingers from getting pinched.
Flip the crab over on its back. Its best to grab them from their rear end to avoid their claws.
Hold the crab down with your hands so it doesn't flip over. Do your best to hold down the claws without getting pinched.
Examine the tail located at the rear end. The tails fold and point toward the abdomen of the crab. If it is a male crab, the tail will be thin and triangular shaped. Female crabs have a much wider fan shaped tail that covers part of the back legs. Females need this large tail to brood embryos.
Flip the crab over and let it go when you are finished looking at it.