The goliath birdeater is the heaviest known spider and can weigh up to 170 grams (6 ounces), about the same as a regulation pocket billiards (pool) ball. Its enormous body reaches up to 12 cm (5 inches) in length and is about the size of a human fist. Its eight legs span some 28 cm (11 inches) and are bested in length only by those of the giant huntsman spider.