 The smallest amphibian ( and vertebrate ) in the world is a <unk> frog from New Guinea ( Paedophryne amauensis ) first discovered in 2012 . It has an average length of 7 @.@ 7 mm ( 0 @.@ 30 in ) and is part of a genus that contains four of the world 's ten smallest frog species . The largest living amphibian is the 1 @.@ 8 m ( 5 ft 11 in ) Chinese giant salamander ( Andrias davidianus ) but this is a great deal smaller than the largest amphibian that ever existed — the extinct 9 m ( 30 ft ) <unk> , a crocodile @-@ like temnospondyl dating to 270 million years ago from the middle Permian of Brazil . The largest frog is the African Goliath frog ( Conraua goliath ) , which can reach 32 cm ( 13 in ) and weigh 3 kg ( 6 @.@ 6 lb ) . 
