Biggest Eel: The Largest Eels by Length and Weight

The biggest eel by weight is the European conger, Conger conger. Wikipedia gives a maximum weight of roughly 72 kg (159 lb), possibly up to 160 kg (350 lb), and a maximum length of around 3 m, although most congers are about 1.5 m and 2.5 to 25 kg.

The answer changes if you mean length. The slender giant moray, Strophidon sathete, is the longest moray: Wikipedia records a fish caught on the Maroochy River in Queensland in 1927 that measured 3.94 m (12 ft 11 in). It is much thinner than a conger, so it weighs far less.

So there are two record holders, and most lists mix them up:

• Heaviest: European conger
• Longest: slender giant moray
• Heaviest moray: giant moray, 30 kg (Wikipedia)

Sizes are the maximums each source gives; one exceptional fish can sit far above the typical adult.

• European conger (Conger conger), eastern Atlantic and Mediterranean: about 3 m and 72 kg (Wikipedia)
• Slender giant moray (Strophidon sathete), Indo-West Pacific estuaries and muddy bays: 3.94 m (Wikipedia)
• Giant moray (Gymnothorax javanicus), Indo-Pacific reefs: a little over 3 m and 30 kg (Wikipedia)
• Green moray (Gymnothorax funebris), western Atlantic from New York to Brazil: 2.5 m (Wikipedia); A-Z Animals gives 8 ft and about 65 lb
• American conger (Conger oceanicus), western Atlantic: 6.5 ft and 88 lb (A-Z Animals)
• Giant mottled eel (Anguilla marmorata), rivers from East Africa to French Polynesia: 2 m and 20.5 kg, the largest of the freshwater eels, family Anguillidae (Wikipedia)
• American eel (Anguilla rostrata): 4 ft and 17 lb (A-Z Animals); see American eel

The electric eel would sit near the giant mottled eel at 2 m and 20 kg (Wikipedia), but it is not a true eel, so we list it separately below.

Conger weights vary more between sources than any other eel:

• Wikipedia's European conger article: roughly 72 kg, possibly up to 160 kg
• Wikipedia's Conger genus article: body weight can reach over 57 kg (126 lb)
• A-Z Animals: reports of exceptional fish up to 240 lb, with claims of anything larger marked as unverified

None of these sources says which individual fish its top figure comes from, so treat the highest numbers as unconfirmed. When you see a single 'biggest eel ever' figure, check whether it is a verified weight or an estimate.

Several big 'eels' belong to other groups entirely:

• Electric eel: up to 2 m and 20 kg. Wikipedia says electric eels are not closely related to the true eels (order Anguilliformes) but are knifefish, order Gymnotiformes. See electric eel.
• Wolf eel: not a true eel either; see wolf eel.

A quick check for morays: a moray has no pectoral fins at all and a small round gill opening instead of a gill cover (Florida Museum, via our moray eel page). If a big eel-shaped fish has fins behind the head, it is not a moray. Our eel fish page covers the other tests.

They can be. Wikipedia's European conger article says congers can be aggressive to humans and that large ones can be a danger to divers. Its Conger genus article records a 2013 attack on a diver in Ireland by a conger more than 1.8 m (6 ft) long and about the width of a human thigh.

Congers are nocturnal predators of fish, cephalopods and crustaceans, living on rough, rocky, broken ground (Wikipedia). Divers should keep their hands out of holes and crevices they cannot see into.

None of the sources we checked records eels as a regular cause of human deaths. The two real hazards come from different fish:

• Eating a moray: large morays at the top of reef food chains build up ciguatera toxins. Wikipedia says eating a giant moray, especially the liver, can cause illness, coma or death, and the green moray can also cause ciguatera and is usually avoided as food.
• An electric eel's shock: Wikipedia calls Electrophorus voltai, at 860 volts, the strongest bioelectricity generator in nature, and records Alexander von Humboldt watching electric eels stun two horses that then drowned in 1800. It records no human deaths.

If you or someone else feels ill after eating reef fish, including numbness, tingling, vomiting or a slow heartbeat, get medical help or call poison control (1-800-222-1222 in the US).

Because eel blood is poisonous. Wikipedia's article on eel as food says eel blood is poisonous to humans and other mammals, and that both cooking and digestion destroy the toxic protein. That is why eel is cooked before it is eaten.

Do not eat raw or undercooked eel, and wash hands and cuts after handling a freshly killed eel. If someone feels ill after eating eel, contact a doctor or poison control.

Moray bites do happen, but usually for a reason. Wikipedia says the giant moray is not usually aggressive but may bite if it is threatened, cornered or when food is around, so feeding fish near a moray or reaching into its hole raises the risk. The green moray is not generally considered aggressive to divers or swimmers (Wikipedia).

Wikipedia says they are the only animals known to use a second set of jaws in the throat, the pharyngeal jaws, to seize prey and pull it in. The open, gaping mouth people see on reefs is not a threat; it is how a moray pumps water over its gills (see our moray eel page). Any moray bite needs cleaning and a doctor's check.

Research and drafting for this page were assisted by AI and checked line by line against the sources listed below. Every number names the organisation or publication it comes from; where sources disagree we say so rather than pick one silently. Records, rules and advisories change, so treat 25 September 2026 as the date we checked them. If you find an error, tell us and we will correct it.