Either way, a steady diet can assist certain crab species in growing to incredible sizes. The biggest crab in the world, the Japanese spider crab, is capable of achieving a leg span of more than ...

With a leg span of 13 feet (4 meters), the Japanese spider crab (Macrocheira kaempferi) is the biggest crab in the world. It lives in the Pacific Ocean's mesopelagic (twilight) zone at depths from ...

The giant Japanese spider crab. This is the biggest crab in the world. ANDY TORBET:Their bodies can grow as big as a basketball, and their leg span, from tip to tip, can be up to 4 metres.