Jellyfish come in all shapes and sizes. Most jellies range from less than half an inch (1 cm) wide to about 16 inches (40 cm), though the smallest are just one millimeter wide! The largest jellies are the Lion's Mane Jellyfish (Cyanea capillata), which on average are around 3 feet wide.

What is the biggest jellyfish ever?

The lion's mane jellyfish (Cyanea capillata ) is the largest among the jelly species, with the largest known specimen stretching across 120 feet (36.5 meters) from its top to the bottom of its tentacles.

How big is the largest jellyfish on record?

The lion's mane jellyfish is the biggest of the jellyfish, measuring 120 feet ( 36.5 m ) from top to bottom of its tentacles.