The longest spider is the Goliath Bird Eater which has an 11 inch leg span. Though there is a fabled Chicken Eater which has an illeged 12 inch leg span
Spiders, if I recall, are measured through leg-span (length and size) or by body mass. The largest spider by leg-span has to be the rare Giant Huntsman spider, having a 12-inch leg-span and can reach...