Fish vary greatly in size. The extant whale shark and basking shark exceed all other fish by a considerable margin in weight and length. The extinct Otodus megalodon exceeds all other fish, extant and extinct (excluding tetrapods), in size. Fish in the common usage are a paraphyletic group that describes aquatic vertebrates while excluding the tetrapods, four limbed vertebrates nested within the lobe-finned fish, which include all land vertebrates and their nearest extinct relatives.
This list therefore excludes the various marine reptiles and mammals, such as the extinct ichthyosaur, plesiosaur and mosasaur reptiles (none of which are dinosaurs) and the extant sirenia and cetacea mammals (such as the marine tetrapod blue whale, generally considered to be the largest animal known to have ever lived).
Largest extant fish
Rank Name Binomial name Taxonomic class Known maximummass (tonnes, lb) Maximum length[m (ft)]ImagesSize comparison to human 1 Whale shark Rhincodon typus Chondrichthyes (Cartilaginous fish) 18.8 metres (61.7 ft) 2 Basking shark Cetorhinus maximus Chondrichthyes (Cartilaginous fish) 3 Great white shark Carcharodon carcharias Chondrichthyes (Cartilaginous fish) 4 Tiger shark Galeocerdo cuvier Chondrichthyes (Cartilaginous fish) (unconfirmed) (unconfirmed) 5 Giant oceanic manta ray Mobula birostris Chondrichthyes (Cartilaginous fish) 6 Giant sunfish Mola alexandrini Osteichthyes (Bony fish) 7 Ocean sunfish Mola molaOsteichthyes (Bony fish) 8 Beluga sturgeon Huso huso Osteichthyes (Bony fish) 9 Sharptail mola Masturus lanceolatusOsteichthyes (Bony fish) 10 Hoodwinker sunfish Mola tectaOsteichthyes (Bony fish) 11 Reef manta ray Manta alfredi Chondrichthyes (Cartilaginous fish) 12 Greenland shark Somniosus microcephalusChondrichthyes (Cartilaginous fish) 13 Megamouth shark Megachasma pelagiosChondrichthyes (Cartilaginous fish) 14 Kaluga Sinosturio dauricusOsteichthyes (Bony fish)
Jawless fish (Agnatha)
Hagfish (Myxini) Hagfish are among the most primitive extant vertebrates. There is only one order and family in this animal class. All of the 77 known species have elongated, eel-like bodies but can be distinguished by their downward-facing mouths. The largest form is the goliath hagfish (Eptatretus goliath). This species can range up to in length and weigh to .
Lampreys (Petromyzontiformes)
Lampreys, as with the hagfish, appear eel-like in shape. They have cartilaginous skeletons and have been evolving separately from any other group for over 400 million years. They are predatory and often attach themselves to a fish or other small animal and gradually drain blood and organs. The largest species is the sea lamprey (Petromyzon marinus), which can grow to and weigh .
Armored fish (Placodermi)
The largest fish of the now-extinct class Placodermi was the giant predatory Dunkleosteus. The largest and most well-known species was D. terrelli, which grew almost in length Engelman (2023), using an ellipsoid volumetric method, estimated weights of 950–1,200 kilograms (2,090–2,650 lb) for typical (3.41 metres (11.2 ft) long) adult Dunkleosteus, and weights of 1,494–1,764 kilograms (3,294–3,889 lb) for the largest (4.1 metres (13.5 ft)) individual. Its filter feeding relative, Titanichthys, may have rivaled it in size. Titanichthys reached a length of though in older paper it was estimated at . However, according to a 2023 paper, it would have been the same size as Dunkleosteus.
Cartilaginous fish (Chondrichthyes)
The cartilaginous fish are not directly related to the "bony fish," but are sometimes lumped together for simplicity in description. The largest living cartilaginous fish, of the order Orectolobiformes, is the whale shark (Rhincodon typus), of the world's tropical oceans. It is also the largest living animal that is not a cetacean and, like the largest whales, it is a docile creature that filter-feeds on tiny plankton. With average lengths estimates between , with regional variation in average body size being possible. The largest verified and reliably measured individual was a female individual repoted from the Arabian Sea with a standard length of with an estimated Total length of . The largest maximum possibly attainable size a whale shark could potentially attain is .
The extinct Megalodon is estimated to have been the largest cartilaginous fish as well as the largest fish to have ever existed. It was macropredatory feeding mainly on marine mammals. With maximum total length estimates ranging from . With the 24.3 meter specimen being estimated to have been around in weight.
Ground sharks (Carcharhiniformes)
The largest species of this order is the widely distributed tiger shark (Galeocerdo cuvier). Specimens have been verified to at least but even larger ones have been reported. One specimen, a gravid female caught off Australia and measuring only long, weighed an exceptional . A female caught in 1957 reportedly measured and weighing , although this very outsized shark is not known to have been confirmed.Large tiger sharks . Homepage.mac.com The largest of the "requiem sharks" in the family Carcharhinidae is disputed. In axial length, it seems to be the dusky shark (C. obscurus), at up to and a weight of . However, the bulkier bull shark (C. leucas) has been estimated to weigh about in recent specimens that measured over long.Summary of Large Bull Shark Carcharhinus leucas (Valenciennes, 1839) . Homepage.mac.com The silky shark (C. falciformis) is another contender for the largest requiem shark at a maximum weight of and a maximum length of around . The largest hammerhead shark is the great hammerhead (Sphyrna mokarran), which can reach and weigh at least .Great hammerhead videos, photos and facts – Sphyrna mokarran . ARKive The most species-rich shark family, the catsharks, are fairly small-bodied. The largest, the nursehound (Scyliorhinus stellaris), can grow up to and a weight of at least . Within the Triakidae family, also known as houndsharks, the largest is the heavily overfished school shark (Galeorhinus galeus), also known as the soupfin shark, which can reach up to and . Other large fish in the order are the leopard shark (Triakis semifasciata), with one specimen recorded at in length, and the common smoothhound (Mustelus mustelus) at .
Chimaeras (Chimaeriformes) These odd, often translucent cartilaginous fish are typically quite small. The largest species is the carpenter's chimaera (Chimaera lignaria) of the oceans near Australia and New Zealand. It can reach up to in length and weigh .Chimaera lignaria (Carpenter's Chimaera, Giant Chimaera, Giant Purple Chimaera). Iucnredlist.org
Frill sharks and cow sharks (Hexanchiformes) The largest of the frill sharks and cow shark is the bluntnose sixgill shark (Hexanchus griseus). This large species typically inhabits depths greater than , and has been recorded as deep as . The largest specimen known (caught off Cuba) reportedly weighed and measured long.
Bullhead sharks (Heterodontiformes) These tropical, small sharks are noted for their broad head shape. The largest species is the Port Jackson shark (Heterodontus portusjacksoni) of Australasian waters, at up to long and weighing up to .
Mackerel sharks (Lamniformes)
Most species in this order grow quite large. The largest living species is the basking shark (Cetorhinus maximus) of the world's northern temperate oceans, also the second largest fish. The largest specimen, which was examined in 1851, measured long and weighed . Perhaps the most famous "big fish" is the great white shark (Carcharodon carcharias). Specimens have been measured up to and weighing , with great whites of at least long generally accepted. The common thresher (Alopias vulpinus), can grow to and weigh over , but much of its length is comprised by its extreme tail. Odd and recently discovered giants also live in this order: the slender, sword-snouted goblin shark (Mitsukurina owstoni), with unweighted specimens of up to approximately , and the massive megamouth shark (Megachasma pelagios), up to long and a weight of .Goblin Sharks, Mitsukurina owstoni Jordan 1898 . Homepage.mac.comFLMNH Ichthyology Department: Megamouth. Flmnh.ufl.edu (November 6, 2010)
The largest shark in the fossil record is the megalodon (Otodus megalodon), a colossal Neogene lamniform. The range of estimates of the maximum length for megalodon are from , with a mass ranging from . It is also regarded as the largest macro-predatory fish ever. Another extinct giant was the Ginsu shark (Cretoxyrhina mantelli) a Cretaceous shark that is estimated to have approached 8 m in length and 4,944 kilograms in mass.
Stingrays and allies (Myliobatiformes)
Both the largest species of this order and the largest of all rays is the giant oceanic manta ray (Manta birostris). This peaceful leviathan can reach a weight of , a "disk" width of and a total length of . A related species reaches barely smaller sizes, the devil fish (Mobula mobular). It can grow up to a disk width, a total length of and a weight of at least . The largest stingray is generally accepted to be the short-tail stingray (Dasyatis brevicaudata), found off the southern tip of Africa and Australasia, at up to across the disk and weighing more than . Although there are several large stingrays that at least approach this species' size. One, the giant freshwater stingray (Himantura polylepis), of the large rivers of South Asia, can weigh up to , measure up to in total length and have a disc span of . The largest verifiably recorded was and . Still, they are the largest of all freshwater exclusive (non-anadromous) fish.
Carpet sharks (Orectolobiformes) The whale shark is the largest species in this order, reaching up to 20 meters long when fully mature. No other species in the order even approaches this size. The next largest species is the nurse shark (Ginglymostoma cirratum), which can grow up to across the disk and weighing more than .Nurse Sharks – Nurse Shark Pictures – Nurse Shark Facts. Animals.nationalgeographic.com Sawfish (Pristiformes) Distinguished by a long snout decorated with sharp teeth on the sides, these little-known cartilaginous fish are often reported to attain huge sizes. The definitive largest species is not known, although the smalltooth sawfish (Pristis pectinata) and the green sawfish (P. zijsron), at up to reportedly , respectively, may be the largest. Weights of up to have been reported, possibly for the smalltooth species, but are not verified. The large-tooth sawfish (P. pristis) and freshwater sawfish (P. microdon) can both exceed .
Sawsharks (Pristiophoriformes) Despite sharing a similar appearing snout adapted in both to shred fish prey, the sawsharks are typically much smaller than sawfish. The largest sawshark is the Sixgill sawshark (Pliotrema warreni) of the South Indian ocean, which can grow up to and weigh .
Skates and allies (Rajiformes)
The largest and most diverse order of rays' largest species is the giant guitarfish (Rhynchobatus djiddensis) of the Red Sea and the Eastern Indian Ocean. The top size of the species is and . The largest of the skates is the flapper skate (Dipturus intermedius) along with the blue skate (D. batis) (previously thought to be the same species, the common skate). D. batis can reach and , while D. intermedius can grow up to and weight . In North American waters, the largest is the big skate (Beringraja binoculata) of the Pacific Ocean, growing to , and .
Dogfish and allies (Squaliformes)