There are 60,000 crustacean species in the world, many of which are not big enough to keep us up at night. However, the largest crab legs belong to the Japanese spider crab, which measures an astounding 12 feet from claw to claw. Just its body can grow up to 16 inches, and the entire crab can weigh up to 42 pounds. Its 10 legs are the largest crab legs in the world. The Japanese spider crab can live up to 100 years.

Despite its terrifying appearance, the Japanese spider crab is said to be a gentle giant with a non-aggressive demeanor, despite the scary picture this video paints. They don’t hunt for prey, instead they scavenge for dead animals or plant matter on the ocean floor. Japanese spider crab is considered a delicacy in Japan.

The world’s largest crab is found on the Pacific side of Japan, and not commercially fished at a large scale. If they are caught, it’s with small trawling nets. The Japanese spider crab’s conservation is taken fairly seriously. No fishing is allowed during their breeding season to preserve population numbers.

Largest Crab Legs Readily Available To Buy

The market is not huge for Japanese spider crab outside of Japan, so Alaskan king crab would be the best choice if customers are looking for the largest crab legs available. Alaskan king crab legs are filled with tender, rich crab meat and available fresh or frozen. Their massive size makes these crab legs sure to please if hosting dinner parties or special occasions.

Due to their size and limited availability, Alaskan king crab is on the more expensive side for crab legs. If price is a factor, it would be better to look for smaller, more affordable crabs like snow crabs or Dungeness crabs.

How Does Crab Sizing Work?

The biggest crab legs available to the every-day consumer would be super-colossal or super-jumbo Alaskan king crab legs. Crab sizing can be a little misleading if the buyer is not well-versed in the measurements and labels. One online seafood retailer might use “super-colossal” to describe the same size that another retailer calls “super-jumbo.”

The trick to understanding crab sizes is that they are measured by how many crab legs will fit in a ten-pound order. These measurements provide the foundation for crab sizes like 6/9, 10/12, 12/14, and so on. An order of 6/9 Alaskan king crab legs indicates that there will be 6 to 9 legs per ten pounds. Each leg will weigh about 1 to 1.5 pounds. Numerical crab leg sizes go hand-in-hand with the written labels, so a 6/9 order would likely be described as “super-colossal” or “super-jumbo.” A ten-pound order with 10/12 sized legs would mean that each leg weighs a pound, and would likely be called “olossal,” or “jumbo.”

Image: The world’s largest crab, the Japanese spider crab, held by a human for scale.

  • Take note of our Affiliate Relationships that may exist with this page and companies listed on it.